History of Western Art Essay Example | Topics and Well Written Essays - 1250 words

History of Western Art - Essay Example athedrals, the traditional basilican form which has a central nave flanked with by a twin tower in its exterior an an entrance adored with lavish structures and stained glass window. This era of architecture developed in four stages: early gothic, lancet gothic, rayonnant gothic and late gothic. In early gothic, the use of pointed vaults like in the Notre Dame of Paris developed. Pointed arches evident in the Bourges Cathedral developed during the Lancet period while in the rayonnant era, structures where usually made of glass with a thin skeletal masonry frame. An example is the Saint Chapelle of Paris. The late gothic style is also known as the flamboyant style because of its form of suggesting flames in their structure. An example of this is the Church of Saint Maclou in France. Gothic architecture also spread out of France to other European countries like Italy, Germany and England. The Milan Cathedral in Italy is a perfect example of this style where it is of a classical basis characterized of a vast span and simple arches. In Germany, gothic structures are evident in the Cologne Cathedral which is built on bricks rather than stone. Their style is greatly influenced by France’s gothic structures. The structures in England were subdivided into three stages that is the early English, the decorated style and the perpendicular style. The English style developed in the 12th to the 13th century and is influenced by the Norman architecture. An example of this is the Lincoln Cathedral and the Salisbury Cathedral. The decorated style flourished during the 13th to the 14th century while the perpendicular style developed in the 14th to the 16th century was predominated with vertical lines. A perfect sample is the cathedral located in Gloucester and the King’s College Chapel in Cambridge. Synthesizing, gothic architecture has three distinctive characteristics that are structures with pointed arches, flying buttresses and ribbed vaults that help support the ceiling

Movies and Television Shows Should Include Better Role Models for Their Audiences Essay Example for Free

Movies and Television Shows Should Include Better Role Models for Their Audiences Essay I’m sure it has happened plenty of times. When you finish watching a movie and afterwards feel so inspired. This is often when the movie hero was presented as someone we would like to be or has a personality that we admire. Sometimes it can be other characters that are shown to be â€Å"cool†, attractive, and popular that also inspires us to mimic their personality traits. Movies can also prompt us to try certain activities. Of course this can be seen as the beneficial side of media; the fact that there could be that one movie that has the power to influence someone to become a better person. But like almost everything, there’s a downside to it too. The fact that media can be convincing in positive ways suggests that it can equally convey negative messages as well. The way that movies or television shows portray their characters is something that definitely needs to be paid attention to. The rebellious heroes, senseless social statuses, and unhealthy activities characters engage in are all factors that will influence the audience. Therefore it is important to consider whether it is worth presenting the characters in this way. A large majority of movies are presenting their characters as bad people, yet the people that anyone would find themselves wanting to be. I believe that is wrong, thus movies and TV shows should include better role models for their audiences. Current movies portray violence without consequence, inaccurate representations of social statuses and social interaction, and encourage characters to engage in activities with more harm than good. Many of the heroes in movies happen to be quite rebellious and are often involved in violence. It’s usually the fact that they’re so involved in violence that helps them obtain their cool, heroic status. The characters we see as role models are always showing that violence can be used as a quick fix for conflicts to avoid negative consequences. K. A. Earles states, â€Å"This depiction of violence increases the probability that violence will be one of the first strategies chosen by a child. † Bandura, a professor in psychology at Stanford University demonstrated that preschoolers learn aggressive behavior by watching television. Three groups of children were shown a film n which a man commands a human-sized doll to move, and when it did not he hit the doll with his fists, a mallet, and then rubber balls. In other words, he used violence as an immediate strategy. Group one saw the man rewarded. Group two saw the episode end without reward or punishment. Group three saw the actor receive a verbal lecture. After watching the film, the children in groups one a nd two were seen to behave more aggressively than the ones in group three. This proves that the consequences characters find themselves facing has quite a strong impact on how the audience will act. What encourages violence even more is that it is often carried out by the hero in the story line who is then rewarded for his/her endorsement in violence. â€Å"Such constant exposure to portrayals of physical violence, some of which viewers do not even recognize as violent, may dull a child’s aversion to this behavior. † says K. A. Earles. Reenactments of national worldwide disasters such as terrorism scenes or brutal wars are one thing. But for a fictional superhero to battle and beat his â€Å"enemies† with realistic and bloody dramatizations is not a good way to entertain kids. There aren’t many positive or useful characteristics of the role model heroes for the children to gain besides their â€Å"charismatic† and â€Å"brave† personalities but they express these lovely character traits through violence. They care for the ones who are in danger so they save them with violence. As they stand up to their enemy and begin to battle them they show out their bravery. These heroes are showing young boys that if you are not strong enough, not brave enough to endorse in a physical fight then you are not capable to be someone as amazing and powerful as they are. Physical strength is spotlighted while intellectual strength is forgotten. Sharon Lamb, a professor of mental health at University of Massachusetts-Boston surveyed 674 boys aged 4 to 18 to analyze marketing trends for action figures and movies. This resulted in violence, emotional aloofness, and general hyper-masculinity being the main messages directors of these movies are promoting to young boys. This shows us that there aren’t many useful or healthy things these movies are promoting to their audiences. This only leads me to conclude that directors need to think over the way they are presenting their heroes. Violence is not the only existing strategy. As well as action movies, there are the modern teenage soap operas. I’ve noticed that these programs have a distorted portrayal of the theoretically existing teenage social statuses. There are always the good people and the bad people, the â€Å"cool† people and the â€Å"lame† ones. Although most television programs are to entertain, having a message or lesson for the audience to gain is also important. As mentioned earlier, the way the characters are portrayed is very significant to the audience since they are what influence the audience. There are the more obvious heroes which are the supermen in action movies but the less spotlighted ones in calmer, closer-to-reality programs. In these kinds of films, the â€Å"hero† would be a character the audience finds themselves admiring and looking up to. This depends on the way the characters in the film are presented. A person who our society would admire and want to be has very precise but general character traits; a confident, rich, bossy girl who has an attractive appearance and good leadership skills. It’s practically the same for boys. Society’s image of a picture perfect female or male is neglecting the many other personality traits of a human being that makes them a good and interesting person. Movies present the â€Å"popular guy† typically as someone who is necessarily good at sports for instance, and send the message to younger boys that if they are not good at sports they can’t expect to be at the top of the theoretical social scale regardless of other good qualities they can have. The same goes for girls. These films portray the â€Å"popular† girls as girls who are very narrowed down in their interests. Female adolescents are portrayed as being obsessed with their appearance. † Smart people are shown to be socially unaccepted. â€Å"Intellects are frequently viewed as social misfits. † These movies are encouraging and strengthening society’s distorted image of who the â€Å"popular† kids should be and contribute to a very inaccurate picture of what social interaction and social status is built on in reality. Young girls or boys may start to think that if they are not what the â€Å"cool kids† are presented as in movies, then they will not be successful or liked. This is definitely not the kind of message that should be sent to the younger generations. Lastly, quite a few of the activities characters in movies or TV shows engage in are not healthy and do not set good examples for young teens. The usage of alcohol and drugs is always by the cool, popular kids who will then convince the kids and teens a part of their audience to try them at one point. â€Å"Social Learning Theory suggests that children learn by watching, imitating, and assimilating. † This only proves that the majority of the children that are exposed to media that is practically encouraging alcohol and drug usage will most likely try it in attempt to imitate their role models. Movies propel the idea of these bad habits being â€Å"cool†. With teenagers picking up their first cigarette as early as 14 years of age, evidently there’s a problem. As many parents and adults may have noticed, kids/teens are beginning to have a distorted idea of what sex is all about and media may be the main cause for their way of thinking. Many movies and shows portray it as a normal thing to indulge in, therefore teens are enacting what they see from the media and often end up being pregnant or contracting a sexually transmitted disease. A study was done on 75 girls in which half were pregnant. It was found that the pregnant girls watched more soap operas than the non-pregnant girls and were found more surprised when told that their favorite soap opera characters used any sex protection. According to the National Survey of Children, males who watched more television were found to be more sexually active than the ones who watched less television. â€Å"Television may be a significant contributor to the sexual practices and attitudes of young people. † All of these things may be a part of a movie to show what it’s like out there but there must be some sort of proof of it being a bad thing to no give out the wrong message. Having characters in movies continuously smoking cigarettes and never even considering the consequences of having sex may influence kids in a completely wrong way. All of these reasons strongly suggest that the role models portrayed in movies and television shows can influence the younger audiences in negative ways. If teenagers are continuously exposed to such behaviors their minds will adjust to thinking in a certain way and no matter how hard their loved ones will afterwards try to convince them that these activities are wrong, that these behaviors are wrong, they will not be capable of changing their minds. Dear parents, are you okay with your 14 year old daughter already indulging in sexual activity, and your 15 year old son reacting violently and aggressively to any confrontations? Dear world, do you believe it’s acceptable for young girls to stress about their appearance and feel bad about themselves simply because of the way they look? For boys to believe that sports are what they are bound to engage in to be liked? Directors of movies should start to think how to get society to think differently, rather than encourage its shallow beliefs. Fighting scenes should not be the only entertaining scenes for kids. More creative ways of how to entertain children in a positive way could be thought of. The modern teenage popular kids should all have different interests and be liked for who they are and not what they look like. Pathetic assumptions and senseless social statuses in general should be presented in a brighter way in programs. Unhealthy activities should be portrayed as the bad things to do rather than the â€Å"cool† things. Kids will follow their role models, and if they’re role models are doing good things, it’s likely they will too.

The Great Railroad Strike Essay -- American History

The Great Railroad Strike In the first half of the 19th Century the working class in the newly industrializing American society suffered many forms of exploitation. The working class of the mid-nineteenth century, with constant oppression by the capitalist and by the division between class, race, and ethnicity, made it difficult to form solidarity. After years of oppression and exploitation by the ruling class, the working class struck back and briefly paralyzed American commerce. The strike, which only lasted a few weeks, was the spark needed to ignite a national revolt by the working class with the most violent labor upheavals of the century. Railroads were the big business of the mid-nineteenth century. The rail companies employed thousands of people and ran operations nationwide. The railroad transformed American society from a rural, agrarian society to an urban, industrialized one. The railroads contributed to an economic boom which pulled millions of peasant immigrants from southern and eastern Europe in search of job opportunities and a better life. However, this same industry took advantage of a vast labor surplus and exploited its workers. A record number of immigrants were admitted into the U.S. during the mid-nineteenth century. Attracted mainly by job opportunities and cheap passage from all corners of southern and eastern Europe, a wave of immigrants flooded the American economy. This mass immigration created a labor surplus which produced a marketplace where workers could be hired and fired at will and had to sell their labor for whatever the going rate; labor had become a commodity. Adding to the surplus in available labor was the boom-bust cycle. The depression of 1873 undermined the position of many worke... ...ctuals to the conditions laborers faced. This would lead to the progressive movement at the start of the twentieth century. The railroad was America's first big business. It pulled people from farm labor and individual proprietors to working for wages for a large corporation. Workers were now being treated as a commodity. They were exploited to keep corporate dividends high during an economic bust cycle. In an attempt to stand up to big business small craft unions began to form but they represented a very small segment of the working class. Strike power seemed the only chance to fight backÂâ€"to take a stand for a minimal life-balance. Though the strikes themselves did little to improve things, it brought national attention to the varying middle class as to their labor conditions. This national attention would help launch a new reform movement called progressivism.

Investigation of the Polar Dinosaur Essays -- Exploratory Essays Resea

Investigation of the Polar Dinosaur Today we know through the evidence of fossils that dinosaur and other large reptiles once lived on every continent on earth. If you were a paleontologist in charge of finding fossils where would you look first? In the search for evidence the icy continent of Antarctica would be perhaps the last continent you would think to search. However, during the last twenty years a remarkable number of prehistoric fossils have been found in regions close to the South Pole. Beginning in 1960 with an expedition lead by a man named Spitzbergen, fossilized footprints from non-avian dinosaur showed the region once had a drastically different climate. In the years that followed more fossilized remains were collected in costly expeditions, often to remote areas near the north and South Pole. However, each find can present unique information about physiological adaptations various forms of life made to polar latitude temperatures during the Mesozoic era. An article â€Å"Polar Dinosaurs† by Thomas H. Rich in Science, published in February of 2002, explores the fossil evidence and presents the following ideas about the environment and the types of creatures who lived and adapted to the seasonal conditions present at these polar latitudes. The ice fields of the North Slope of Alaska we know today are thought to have had temperatures ranging from 13-2 degrees Celsius during the Cretaceous period. This hypothesis is based on evidence from flowering plants, and leaf fossils found from the late Cretaceous found in the region. So life around the poles existed in a climate similar to that of Portland, Oregon, which has a mean temperature of 12 degrees, and may have gotten as cold as Alberta Canada’s average of ... ...uld have probably been impossible for life in the Antarctic where a large seaway eventually developed cutting southeastern Australia from Antarctica. The investigation of polar dinosaurs continues with the excavation of a new site in northern Alaska near the Colville River. Paleontologists have discovered a huge, 100 km, slab of rock that spans the last 40 million years of the Mesozoic era. Exploration of this site through tunneling is believed to present a more extensive record of polar dinosaurs as they were over the Jurassic and Cretaceous periods. (1) Works Cited 1) Rich, T.H., P. Vickers-Rich & R.A. Gangloff, February 2002, Polar Dinosaurs. Science 295:979-980. 2) Mayell, Hillary, Researchers Melt Polar Dinosaur Mysteries, National Geographic, Febuary 2002, http://news.nationalgeographic.com/news/2002/02/0225_0225_polardinos.html

What Effects the Bounce of a Dropped Ball

Aim The aim of this experiment is to investigate the efficiency of a bouncing ball, and the factors which affect its efficiency. Hypothesis If I increase the height from which a ball is dropped, then the bounce height will increase because it will increase the speed and create a larger impact, causing the ball to bounce higher then dropping it from a lower height. Materials 1. High bounce ball 2. Measuring tape 3. Tape 4. Wall Risk AssessmentH- Cutting yourself with the measuring tape C- Handle with care and ensure that it is locked Method 1. Hold the measuring tape with the 0 centimeter end on the floor. Then tape the measuring tape to a wall. 2. Hold the bottom of the high bounce ball in place with the 100 centimeter mark on the measuring tape. 3. Drop the ball and determine the total bounce height of the ball, which would be the distance from the surface to the bottom of the ball at the top of its bounce. . Continue till you have data for 3 tests. 5. Repeat steps 2-5 for drop heig hts 80 cm 60 cm 40 cm 6. Average all the data. Variables Independent variable = drop height Dependent variable = bounce height Controlled variables = ball, surface, measuring tool Data Table Height a Ball Bounced From Different Drop Heights DROP HEIGHT (CM) TEST 1TEST 2TEST 3AVERAGE 10050495150 8038394039 6031293030 4022202120 Graph

Review of Nuclear Battery Technology Essay

Review of Nuclear Battery Technology Essay Review of Nuclear Battery Technology Essay Example Review of Nuclear Battery Technology Essay Example The Role of Nuclear Battery for Smartphones In smart phones, batteries play a major role in providing power. Scientists as well as technology firms are continually looking for means to better the life of these batteries and their efficiency. The University of Missouri lately came up with a more efficient nuclear battery that is long lasting. This battery is capable of running several applications including a space flight. They also act as a reliable energy source in automobiles. Search for alternative sources of energy has made scientists indulge in extensive research in almost all fields to gather information on how to tackle the challenge of battery life of batteries used in various devices such as phones and laptops and come up with ones that are more efficient than the existing chemical batteries. The basic idea the researchers have been developing is that instead of consuming or utilizing the power in a battery`s chemical gradient, for instant in Lithium batteries, to employ the energy emitted by the decaying of isotopes of radioactive elements in a natural manner to generate energy. These batteries are referred to as nuclear batteries. Problem definition Nuclear batteries in smartphones emit radiation and in case of a leakage they can cause cancer and even death. For example, the gamma rays which have intense, penetrating power can only be checked with the introduction of a large lead lump; otherwise, cancer is inevitable. The casing is done to reduce radiation in smartphones, and it is done using the materials mentioned. Another possible disadvantage (though it is not common) is that terrorists may use the Strontium-90 to develop dirty bombs even though the substance is very expensive. Radiation protection principles presume that any radiation dose, no matter how small it might seem to be, can harm a person. Nuclear batteries are lighter than other ones, however, they can provide energy for smartphones, and they are much smaller in size as well as more efficient as other batteries. Nuclear batteries also have sufficient energy density. The radioisotope that is an example of nuclear energy can supply energy density that is approximately six orders of magnitude more than the batteries manufactured using chemical substances. Betavoltaic chipsets that are also nuclear batteries are commercially available and are of high demand due to low voltage. They are also amp products for the niche markets such as the military. Betavoltaic batteries generate power from beta radiations rather than photons. These beta radiations are high power electrons emitted by radioactive elements. Several commercial uses of nuclear technologies exist today, for example, fire control detectors and emergency exits in many buildings. Lithium-ion batteries have an aging problem, which becomes evident one year after the purchase and the manufacturers always go silent about this. It always happens whether the battery is in use or kept idle. Another disadvantage of lithium-ion batteries is that they are regarded as not completely mature since the chemicals and metals vary on a continuous basis. They need a protection circuit to preserve the voltage as well as the current within some safe limits . Natural Li is converted into isotopic clear 6Li. The merits of performing this task are the fact that thermal neutron combination of the cross-section is multiple of magnitude order larger than the natural Li cross-section implying that researchers can evaluate factual manufacturing methods and techniques. Functional requirements Terms such as atomic battery, nuclear battery and radioisotope and tritium generator are employed to depict devices that use energy produced from decaying of the radioactive isotope to generate electricity. Conversion method is divided into thermal and non-thermal one. Thermal converters consist of the thermionic and thermoelectric kinds of generators. Their output energy is always a function of a temperature difference. Non-thermal converters output of power is not a function of a temperature difference. It extracts a portion of power as it is degraded into the heat energy instead of using the thermal power to run electrons in the circle. Atomic batteries in most cases have an efficiency of between 0.1 to 5%. High efficiency beta voltaics have an efficiency of 6-8%. Thermal converters are classified into a thermionic converter that includes a hot electrode that emits electrons in a thermionic manner over a potential power barrier to a relatively cool form of an electrode and produce valuable electric energy output. Cesium vapor is employed to highly optimize electrode task function as well as present an ion supply to make sure the electron space charge has been neutralized. Beta voltaic is a battery that generates energy from radiation and scientists have studied the battery since 1950 and regard it as a major source of nuclear energy. Day to day research is being pursued on nuclear batteries in various research institutions. Much of this task is centered on making the frontiers of these nuclear device technologies by using energy sources with the help of beta or alpha particle decay, which is based on the radioactive isotope emitted. The area of the beta voltaic, which is the most tackled by the researchers, is tritium. This is a hydrogen isotope that has a pair of neutrons and a single proton as well as electron inherent in its hydrogen form. It is a radioactive isotope with a half-life of 12.32 years during which it emits beta particle that is basically an electron. This makes it more preferred over other known solutions that emit dangerous gamma radiations . There are several other advantages of tritium like its weight; it is arguably the third lightest among the existing isotopes. It also has properties and reactivity similar to those of hydrogen. Researchers are well conversant with its production path, and they are also quite aware of its hazards. A specimen of Highly-Oriented Pyrolytic Graphite (HOPG) that is intercalated with some lithium so as to check loading before irradiation occurs. Nuclear energy sources when controlled arent inherently dangerous. These nuclear batteries employ radioactive isotopes referred to as strontium-90. The latter improves the electrochemical power in water-based solutions. An electrode consisting of nanostructured titanium dioxide and a coating made of platinum is responsible for converting the energy or the power into electrons . The water operates as a buffer. Surface Plasmon developed in the device emerges as a useful component since it improves the batterys efficiency. The Ionic solution, however, cannot be easily frozen at minimal temperatures. It could efficiently perform in a variety of applications, for instance, car batteries. Constructing a betavoltaic device, a silicon material inside two electrodes is wedged. By the time the radiation strikes the semiconductor there is a production of electrons flow, simply referred to as voltage electricity. Unfortunately, ancient materials were less suitable for enormous stacked arrays since the volume and the mass of the battery being developed would be large. Thinner and relatively lighter collectors and emitters were required for designing an array. Of late, developments in graphene are still to be correctly integrated into the architecture of this betavoltaic. When correct integration into these thin stacked kinds of betavoltaic arrays is completed, a wider utilization and efficient performance would be experienced. It is possible that betavoltaic energy can generate more power as compared to chemical batteries. The anticipated maximum efficiency of promethium and tritium batteries is 21% and 12% respectively. Factors leading to these efficiencies are the source construction and the secondary electron discharge as well as backscattering mainly from the collector. Experimentally, it was demonstrated that the efficiency of the tritium direct charge battery model with vacuum dielectrics and collectors with secondary electron emission suppression and backscattering coating reached 5.5%. This kind of battery has an activity of curies of approximately 108. The experiment also demonstrated a voltage of 5300 volts with short circuit current of 148 nanoamperes. However, the efficiency can be doubled with a double-sided source. A promethium-147 nuclear battery has an activity of above 2.6 curies. The experiment shows it generates a voltage of 60kv. The current for the short circuit is 6.0 nano-amperes reaching an efficiency of 15%. The effect of charge accumulation in dielectrics under mono-energetic electron beam irradiation was used for developing nuclear batteries. In this battery, the charge accumulated on the surface conducts electric current through an uncharged dielectric. A nuclear battery was fabricated and tested with a tritium source; taking into consideration that a dielectric layer is wider than the range of tritium beta elements and a metal collector is without a vacuum space, this model generated 0.4 microwatts of electricity. Natural radioactivity emits radiation that generates energy. Nuclear batteries also known as atomic batteries harness the energy. The power density of the final product and the application domains depend on a material employed to generate that energy. On the other hand, the output and the potential efficiency of the battery depend on the form of conversion employed. Thermal converter, that is a radioisotope generator, utilizes the thermal energy produced by radioisotope decay to generate electricity. Methods used for this process include thermocouple heating, a recognized charge accumulation effect found in the dielectrics. The nuclear batteries developed at the Missouri University consist of a platinum-coated titanium dioxide electrode that was with. Water was also incorporated in addition to radioactive strontium-90. Sr-90 can decay radioactively with 28.79 years half-life. It generates an electron referred to as beta radiation; it also produces anti-neutrino as well as the isotope yttrium-90. This Y-90 has a half-life of 65 hours. This causes decay of additional electrons and anti-neutrinos. Stable Zirconium is also generated as a result of the decay. The wisest aspect of employing Sr-90 as a source of energy is the fact that it emits less or zero gamma radiations. Nuclear batteries are safe to handle and also very easy to use. Apart from being used in smartphones they are used extensively in health departments, for example, for cancer radiotherapy . Design concept Safety of radioactive substance is ensured by introducing an aluminum material between a human body part and the source of the rays. Thus, the safety of betavoltaic is checked in this way to avoid damage to people. One of the greatest advantages of nuclear batteries in smartphones is the fact that recharging will not be done as in the case with chemical batteries. As mentioned above, nuclear batteries with efficient packaging possess an energy density that is greater than in chemical ones. Additionally, the radioactive isotopes used to develop nuclear batteries are easily available at affordable market prices. Nuclear cells have a life span not less than ten years. This is an overwhelming term as they supply energy to equipment non-stop. Thus, the reliability and the longevity incorporated together may suffice a minor power needs for a decade. However, radiation safety standards need to be met. Incorporation of safety measures to ensure nuclear batteries are safe to handle. Devices, like smartphones batteries emit nuclear radiation that includes beta and gamma ray beams. This radiation is however kept in closed packages. Individuals worry that tritium in these batteries may diffuse due to the small size of the package and its mobility. They fear that it could diffuse through graphitic matrix, due to the complicated process of covering it . The worry for this is counterattacked by the fact that it is experimentally proven that the radiation would remain in the matrix as long as the temperatures remain below 627 degrees Celsius. The operating environment temperature that people live in is far much below this limit. The remaining challenge is the moisture. Nevertheless, the scientists are making use of a robust, hermetically fastened package. In less than three years to come, research companies, if funded adequately, will produce nuclear powered devices for general market. On this time framework, though, the researchers argue that it would depend on the regulatory framework. The addition of water was arguably the breakthrough of these batteries since that water can absorb a great amount of beta radiation since when in large quantities it can detriment to a betavoltaic semiconductor. However, beta radiation rips apart the molecules of water, generating free radicals as well as electricity. Comparative study with previous concept The cost of developing these nuclear batteries is relatively high. As for the case of most innovations, the starting cost is rather huge. However, as the innovation goes operational, these drawbacks varnish as the product is produced in bulk. Nuclear batteries for some specific applications like the size of laptop batteries may lead to some problems though it can be eliminated as time progresses; for instance the Xcel in laptops batteries is much more compared to the conventional one. Prospective commercial application of nuclear batteries in smartphones The aerospace firms would welcome smartphones recharging themselves. Oil and the gas companies are also potential commercial markets for the nuclear batteries due to their recharging factor. All these companies require some reliable energy sources in physical extremes for instant low temperatures and low pressure . The betavoltaic battery integrated into a flight data detector may signal to the searching squad for years rather than months. The odds of coming up with a commercially viable substance are reasonably perfect since the ultra-thin kind of collectors exists anyway. There is a growing global interest in the development of these thin beta-electron kinds of emitters. Applications Nuclear batteries are used widely due to their long life capability and high efficiency. This sort of innovation will undoubtedly change the current technology for the better and eliminate the power limitations brought about by chemical cells. In space applications, nuclear energy units are more significant as compared to the solar cells and the ordinary chemical batteries. Solar cells are easily destroyed when passing through radiation areas. The second reason is that the operations on planets such as Mars and the moon, where long phases of darkness need heavy batteries to provide power. Solar cells can only get energy from the sun. The third is that the missions conducted in space in an opaque atmosphere for instant on Jupiter. There is no light there, thus solar cell are useless there. The nuclear source of power would be useful in space. Nuclear batteries would also eliminate the necessity of heating electronics in areas where temperatures are -245 degrees Celsius, for instance in space. These incredible advantages would ensure the nuclear batteries will easily replace current chemical sources of power. All applications including the phones that require large powers and a high lifetime and not forgetting a definite design over density will automatically prefer the nuclear source. The other application is the use of these batteries in mobile devices. A nuclear-powered battery for a laptop or a phone can provide supply approximate 8,000 times the life of the ordinary laptop or phone battery. Nuclear brings about forgetting the tedious process of recharging and replacing batteries. A nuclear battery through research has been found that it can endure a minimum of five years. The Xcel-N has never been switched off since it started its operation. It has been working for eight months in a row, without using any external energy supply. Low energy electronics are ending up being versatile. Therefore, these kinds of batteries are nowadays becoming commercially relevant. They act as power sources for machinery that ought to function unattended for a long time, like satellites. Also, if it packed correctly, it can be applied to spaceship and pacemakers. These batteries can provide energy to a variety of objects from the tiny sensors to enormous systems. The plans of these nuclear batteries A proof-of-principle form of analysis starts with an emitter. Irradiation of the high-energy grapheme-based kind of beta emitters is necessary. When this is fully optimized, then invention and development of nuclear powered cells is quite possible. The key hurdles are experienced in the transportation of these devices and their handling. It is advisable to collaborate with Defense Advanced Research Project Agency (DARPA) in developing the geometry, and in field-testing of these devices . Feasibility assessment The above-mentioned researches concerning the nuclear batteries present adequate hope in the supply of power and energy in future for devices and applications. Upon implementation of these technologies, feasibilities and credibility of devices such as smartphones will be elevated. This calls for keen observation of all standards while producing nuclear batteries so as to avoid the leakage of radioactive substances. Economic feasibility will be dictated by advantages and its applications. With a variety of features being added to these researchers, nuclear batteries will undoubtedly be one of the greatest inventions made in human history. Dose calculator Since we live in a radioactive universe where radiation is a part of the natural environment, its essential to measure the radiation dose. The unit used to measure is known as the millirem (mrem). The regarded annual dose in every person should be around 350mrems, whether it comes from a natural or a man-made source. It is nor desirable for any individual to receive more than that dose annually. Absorbed dose refers to a quantity of radiation experienced by a person in the body. The absorbed dose units are (rad) and gray (Gy). Dose equivalent adds together the radiation quantity that is absorbed with the medical effects of that radiation type. For the beta and the gamma rays found in smartphones have the same dose equivalent as the absorbed dose. The dose equivalent for these rays is much higher than those of the neutron and the alpha. This is because these types are more harmful to human body. The dose equivalent units are the roentgen man (rem) and the sievert (Sv). The biological equivalent of the dose is estimated in 1/1000th of a rem, which is known as millirem. For practical purpose, 1R (exposure) = 1rad (absorbed dose) = 1 rem or 1000mrem (dose equivalent). A measure presented as Ci shows substances radioactivity. A measure in rem or mrem indicates the energy amount that is deposited in living tissues by a radioactive substance. Nuclear energy source will replace conventional cells as well as the adaptors; hence, the future will be full of exciting innovations with new ways of powering the portable devices. Although automobiles are in the first phase of their development, it is a clear indication of how nuclear energy is being employed. It is highly promising that the nuclear cells will definitely find a niche in automobiles and issues like running out of fuel or the battery life will come to an end. Though they pose a negative effect, the advantages brought about by nuclear batteries outweigh the disadvantages. The good thing is that these demerits are controllable. In future, the world of science will continue to use electric power from indispensable radioisotope. The scientific world argues that small devices ought to use small batteries to supply them with power. The urge for extra power arises as technology improves.

Out of this Furnace essays

Out of this Furnace essays The book Out of This Furnace by Thomas Bell expresses a story of the triumph of man over his place in society. It illustrates this point through the story of George Kracha and his offspring and their struggle to adjust to the world they had arrived in. Their new home was an unforgiving place. It was filled with ignorant people who were not tolerant of the new peoples coming to share their homeland. Thomas Bell, author of Out of This Furnace, grew up in the steel mill town of Braddock, Pennsylvania. He drew on many personal experiences to create a full picture of the environment in which the story takes place. This fictional portrayal of the steel mills is based on the true history of steel production over three generations beginning in 1881. Bell illustrates the lives of the steel workers and the conditions under which they live and work. Firstly, the living conditions in these mill towns were appalling for the steel workers. They lived their lives working as hard as they could, for someone else. In those days, as well as in these days, the very system of work and money was geared to keep lower class down and keep higher class up. This is called capitalism; the method of governing that allows unlimited accumulation of wealth and properties. In fact, this is a horrible way to govern the masses. Because of this premier principal of capitalism, it is possible to state that this system of government ifs faulty. The fault begins in the fact that not all classes are equal; the higher classes would have the lower classes believe that they live in the same station of life as them. When in fact, the very idea of capitalism is what draws the separation of the classes. It becomes a situation where the labor of the lower class keep the upper class afloat, yet the upper class holds all the power in voting and through other methods. . Bell portrays initial worker interest in forming these unions, yet the representatives had a ve...

50 Words for Writing

50 Words for Writing 50 Words for â€Å"Writing† 50 Words for â€Å"Writing† By Mark Nichol As an unabashed proponent of reasonable elegant variation the moderate use of synonyms to avoid tiring repetition of a specific word throughout a passage I offer this assortment of terms for a piece of writing: 1. Article: This word, with the diminutive -le as a clue, refers to a small part of a publication (thus, the extension of the word to mean â€Å"thing† or â€Å"item†) more specifically, a piece of nonfiction that appears in a periodical or on a Web site. (It also refers to a section of an official piece of writing.) 2. Brief: Breve, the Latin predecessor of this synonym for short, acquired the connotation of â€Å"summary† or â€Å"letter† when it was used in the Roman Catholic Church to refer to a missive less extensive than a bull. (That word comes from the Latin word bulla, â€Å"knob,† referring to the seal that ensured discretion.) Brief now refers to a legal summary hence briefcase. 3. Causerie: This noun form of the French verb causer, â€Å"to chat,† directly borrowed into English, means â€Å"a brief, informal essay.† 4. Chronicle: This term, derived from the Greek term ta khronika (â€Å"the annals†), refers to a an account of a succession of historical events. 5. Column: This word originally referred to a vertical block of type on a page, echoing the original meaning of â€Å"pillar.† Early journalistic publications, which made no pretensions to objectivity, laid out various pieces of writing in distinct columns, hence the modern connotation of an article advocating a point of view. 6. Commentary: The Latin term from which this word derives, commentarius, refers to personal writing, but the modern sense is of an opinion piece. 7. Composition: This descendant of the Latin word compositionem (â€Å"putting together†) refers to the assemblage of sentences that constitutes a written effort, either in general or in the specific reference to a scholastic exercise. 8. Critique: A critique, as the name implies, is a work of criticism; the connotation is of a formal, erudite dissection of another written work (or any creative endeavor). 9. Diatribe: Interestingly, this word’s Latin precursor, diatriba, has the neutral connotation of â€Å"learned discussion.† A couple hundred years ago, it acquired the sense, now exclusive, of harsh criticism or complaint. 10. Discourse: The meaning of discursus, the Latin term from which discourse stems is â€Å"the act of running around,† suggesting the process of progressing through a written argument. 11. Discussion: Despite the resemblance of this word to discourse, there is no relation; the Latin origin is discussus, meaning â€Å"to break apart,† which led to the noun discussionem and its sense of â€Å"examination.† 12. Dissertation: The term from which this word’s Latin ancestor, dissertationem, is ultimately derived means â€Å"to take words apart†; the primary sense now is of scholarly writing that examines or debates an assertion. 13-14. Document: The Latin term documentum (â€Å"example, lesson, proof†) now has a generic sense of any piece of writing. Documentation, however, implies information provided to support or authenticate other writing, and is used especially in computing and in academic research. 15. Editorial: This word derives from the direct borrowing of the Latin term editor (â€Å"one who presents†). As the entry for column explains, all editorial content was originally subjective, but in modern journalism, the term refers to a statement of opinion by a periodical’s management or by a guest commentator. The latter variety is often relegated to an op-ed page. (The latter term is an abbreviation for â€Å"opposite the editorial page† that being the sheet on which the publication’s own arguments are printed.) 16. Essay: The meaning of this word is â€Å"attempt† (it’s related to assay, which refers to a test of a metal’s purity), with an original connotation, long since muted by the quotidian ubiquity of the scholastic assignment by that name, of a written opinion presented for the audience’s approval. 17. Examination: The sense of â€Å"test† for this word (or for exam, the truncated form that has largely supplanted it) follows the original meaning of â€Å"test or judging in a legal context† (hence the judicial term cross-examination). 18. Exposition: This word derived from the Latin term expositionem (â€Å"something shown or set forth†) can mean â€Å"narration† or, more often, â€Å"explanation; the latter sense is employed in literary criticism to refer to the author’s technique in revealing background details. 19. Feature: This term, taken from Latin by way of French, means â€Å"a formation.† In writing, it refers to an article specifically, usually a profile of a person, place, or thing, perhaps with a more conversational style, as opposed to a more straightforward news or informational piece or an opinion. 20. Guide: This word from the same term in French, originally meaning â€Å"one who shows the way,† refers to publications that inform readers about how to do something or where to visit. It may be extended to guidebook. 21. Memorandum: Taking directly from the Latin word for â€Å"(thing) to be remembered,† this word, and its abbreviation, memo, refer to an official note. 22. Minutes: This word, which stems from the Latin phrase minuta scriptura (literally, â€Å"small writing†), refers to a record of a meeting or a similar event. 23. Monograph: This word, which literally means â€Å"writing about one (thing),† refers to academic writing on a topic. 24. Narrative: The Latin term narrationem means â€Å"recounting,† and this word is a synonym for â€Å"story,† though it also specifically refers to storytelling style. 25. Polemic: This Anglicization of the French word polemique (â€Å"controversial†) means â€Å"a harsh response to or refutation of an opinion.† 26-28. Paper: This meaning an example of synecdoche, in which the name for a material stands in for something made of that material (as in wheels as slang for car) describes a scholarly written presentation. A variation is white paper, a piece of writing prepared for or by a government entity or a business to inform or persuade. By contrast, a green paper is a preliminary version of a white paper. 29. Proces-verbal: This French term meaning â€Å"verbal trial† is an unnecessary synonym for report unless, perhaps, one wishes to mock the formality or pretension of a report. 30-33. Prolegomenon: This mouthful of a synonym for preface, taken directly from Greek, means â€Å"to say beforehand,† though it may be used in a more general sense than preface, which usually refers to a specific component of a book. (A book preface, by the way, is distinguished from the proximately placed foreword by the fact that it is the author’s statement of purpose, intended audience, scope, and content. A foreword, by contrast, is a recommendation from another person. There may also be an introduction, which orients the reader to the topic.) 34. Propaganda: This word, stemming from the Modern Latin word for â€Å"propagating,† was used by the Roman Catholic Church in the sense of disseminating the Gospel. Since then, it has acquired a derogatory connotation, referring to true, slanted, or fabricated information designed to promote one’s, or criticize another’s, position or ideology. 35. Proposition: Like many words on this list, proposition comes down almost intact from Latin in this case, from propositionem, meaning â€Å"a statement.† In rhetoric, it is specifically the initial statement of an argument, or a point offered for consideration. It is also employed to refer to a type of referendum. 36. Rant: Alone among all the words on this list, rant is from a Germanic language, rather than Latin or Greek: Randten means to talk foolishly, and a rant is an emotional and perhaps irrational criticism in speech or in writing. 37. Report: This translation of the Latin word reportare, meaning â€Å"to carry back,† in noun form refers to a written or spoken account. More specifically, it acquired the sense of an investigative summary and, by extension, a scholastic exercise. 38. Review: This word, from the Latin verb revidere (â€Å"to see again†) by way of French (as the noun reveue) is used as a less formal synonym for critique (a written evaluation of a creative product). 39. Screed: This word (from the Old English term screde, â€Å"fragment,† and related to shred) needs context assistance, because it can mean â€Å"informal writing,† â€Å"a long speech,† or â€Å"a rant.† The last sense is the most frequent, but make sure, whatever usage you intend, that your readers will understand your intent. 40-41. Script: This derivation of the Latin word scriptum, â€Å"a piece of writing,† is versatile. It can refer to a piece of writing in general, to a set of instructions, or to a copy of a play, a screenplay, or a similar work, as well as to a brief computer program. It also has an informal connotation of an orchestrated version of reality that all associated parties are expected to adhere to. Manuscript literally means â€Å"a piece of writing produced by hand,† though now it has the more general meaning of a draft of writing at any stage of preparation, as opposed to a published version. 42. Study: Based on the Latin term studere, â€Å"to be diligent,† the verb gave rise to the noun meaning â€Å"evaluation† or â€Å"experiment† and then to a sense of a written account of the procedure. A case study is an account of a particular person, event, or situation. 43. Testament: Testamentum, in Latin, means â€Å"will,† as in the legal document, as does the English derivation, but it can also mean â€Å"a supporting statement.† 44. Testimonial: This word, derived from the Latin term testimonium, which originally referred to biblical scripture, came to mean â€Å"an attestation of the virtues of a person or thing.† 45. Theme: This word comes from Greek, meaning â€Å"something set down,† and is akin to thesis (see below), though it often refers merely to a student composition. 46. Thesis: Thesis stems from the same Greek root as theme (tithenai, â€Å"to set†); the former word, like the latter, means â€Å"something set down.† The formal meaning is of a piece of writing produced as a requirement for a college degree, but it also has a general sense of â€Å"a statement to be proved† and as such can refer to an introductory argument in a larger work. 47. Tract: A truncation of the Latin term tractatus, â€Å"a treatment,† tract has an often pejorative sense of a piece of propaganda (see above) or something reminiscent of such, often in pamphlet form. 48. Treatise: This word stems from a French derivation of the Latin term tractatus (see above) and refers to an argument that discusses and analyzes a topic. 49. Treatment: Treatment, which has the same root as treatise, is usually employed to refer to an outline or early adaptation of a screenplay. 50. Write-up: This informal term for a piece of writing can carry a connotation of a work with an unduly positive bias, so take care that the context communicates this intent or the lack thereof. Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Vocabulary category, check our popular posts, or choose a related post below:36 Adjectives Describing Light34 Writing Tips That Will Make You a Better WriterOne "L" or Two?

How Technology is Changing the Face of Business Today 1 Assignment

How Technology is Changing the Face of Business Today 1 - Assignment Example Therefore, the most critical business processes that largely use information system in Coca Cola Company include customer service and communication. In retrospect, productivity is improved because employees perform their roles and responsibilities with ease when dealing with customers. Additionally, efficiency and transparency is increased when information systems are constantly used in conducting business particularly in issues of marketing (Abrams, 2003). Overall, production processes remain the greatest beneficiary of new technology platforms used by Coca Cola. In Coca Cola Company, IT is the driving force that makes business process faster, cheaper, and more accurate. This is through new communication formats that are easy to manage between the clients and the management. For example, the use of social media forums, text messaging, and teleconferencing ensures that customer-savvy customers are better in selecting their preferred goods and services (Roberts, 2011). It also improves their choices and decisions when giving a feedback or

Why markets generally fail to achieve social efficiency Essay

Why markets generally fail to achieve social efficiency - Essay Example On the other hand, if the marginal cost to society exceeds the marginal benefit, then the social efficiency is low in that case. Whereas, when MSC and MSB are equal, it is referred to be at an optimum level (Suneja, pp.147, 2000). It is very difficult to achieve social efficiency and real markets fail to accomplish it because their marginal social costs do not equal the marginal social benefits. There are a number of reasons behind market failure. Externalities: â€Å"A market is not likely to lead to market efficiency if the deeds of the producers or consumers affect people other than themselves† (Sloman & Sutcliffe, pp.430, 2004). Externalities occur when society fails to make adequate compensation for the production of goods and services as well as for the consumption of these products. This is attributable to the ‘spillover effect’ this leads. Since the pricing system does not account for the marginal social costs and benefits that are attached to the compensa tion of these products, externalities exist, which may often lead to market failure. Social cost is the addition of private cost and the externalities. Let us take an example of a chemical industry. If a chemical industry release by products into a river or atmosphere, it is creating negative externalities that

Early Greek Legacy - Choice of topics listed Essay

Early Greek Legacy - Choice of topics listed - Essay Example did not have any belief in material image of God- no creature can represent the creator. Whereas in Eastern religions like Hinduism, the material images of God is worshiped. They believed in the personality of human of being in God like he could be angry, even jealous, but his primary attributes were righteousness, justice mercy, truth and faithfulness. He is represented as king, Judge and shepherd. Whereas in Hinduism various deities are worshiped at shrines; the divine trinities, representing the cyclical nature of the universe, are Brahma the creator, Vishnu the preserver, and Shiva the destroyer. The first books of Hebrew law contain legal writings of Exodus, Leviticus, and Numbers. The fifth book of the Bible was called Deuteronomy [Second Law] primarily a report of the last words and deeds of Moses. It contains numerous laws, often in the context of interpretation and preaching whereas Hindu law preaches the birth, death and rebirth of living things, and its precepts cover many more activities than does any secular legal system. The Hebrew people gave Torah special reverence than the portion of the Hebrew Bible because the written Torah which consists of the five books of Moses, Genesis, Exodus, Leviticus, Numbers, and Deuteronomy .The scrolls are considered mostly holy. Whereas the Hebrew Bible which is also called as the Jewish Bible even though it consists of Hebrew Scriptures, 39 books originally written in Hebrew, except for a few sections in Aramaic, the script of Hebrew Bible was not given importance while compared to Torah which valued the tradition without any modification. In the case of the covenant between God and the Hebrew people, God’s obligation is conceived as the defense or vindication of the people .His righteousness is shown by his saving arts [see, for instance ,psalms 98:2;Isaiah 51:5] Hebrew’s obligation on the other hand ,is to obey the will of God as disclosed in the Torah, the law. Yes, each party honored the

Business Process Modeling Approaches Article Example | Topics and Well Written Essays - 500 words

Business Process Modeling Approaches - Article Example Paul Harmon comes in to provide much simpler, quicker, less expensive yet equally beneficial ways of improving the performance of one’s business. Paul picks up from Rummler and Brache who introduced a very straight forward modeling approach (Harmon, 2003). They named this approach Process Mapping. The Process Mapping model was further developed to form the Unified Language Modeling and later into the Business Process Modeling Notation. Paul argues that these models involve the use of extra work and he tries to simplify them while at the same time ensuring that the end results will be equally worth it. He starts by saying that any business that wants to carry out a business process modeling needs to identify its current position, reasons for the remodeling as well as what it wants to achieve at the end of the process. In his book Business Process Change, Paul picks up on the Unified Modeling Language to describe and uses it to describe various business processes that may need remodeling if a business is to improve its efficiency. Here, Paul identifies different levels of business process from external processes, top-level processes down to the junior-level processes where roles have been assigned to various junior officers in the company. He says that it is important for every business level to be remodeled if the company wants the best results from the whole business modeling process (Harmon, 2003). Paul Harmon brings out various business modeling diagrams that are essential for a business to have. He introduces that ‘is diagrams’ which reflect the company’s current position, the ‘could diagrams’ which indicate the company’s targets and that ‘should diagrams’ which are a must attain target for the company. He recognizes the need for a business to integrate human activities and information technology (IT) activities in the modeling process for best results. According to Paul, any efficient

Engineering business functions Assignment Example | Topics and Well Written Essays - 750 words

Engineering business functions - Assignment Example For instance, the purchases Department are directly linked to the plant processing company. It is the purchases department that works towards ensuring that the raw materials are available for processing in the plant. The purchased parts of the automobiles are processed to form the end products that are sold. Again, where there is a delay in the purchases, the output will reduce. At the same time, when there is a problem with the finance department, there will be reduced efficiency in the purchasing department that will eventually be reflected in the output in the organization. However, efficiency in the finance department will also lead to efficiency in other operations given other factors are always kept constant. Additionally, the production process relies heavily on other important factors. For instance, for effective production, the mechanical processes involved must all be efficient. The required expertise must always be availed to monitor the whole task otherwise that will occu r some errors. Moreover, if the sales department does not effectively execute their duties, then there will be overstocking that will otherwise result in losses in the organization and reduce the rate of production. The necessity of developing standards is essential. The success of any business lies in achieving the standard that can suit both the customer’s specifications and that of the company. However, determining these specific standards remains the main problem that any firm can ever meet.

Business Process Modeling Approaches Article Example | Topics and Well Written Essays - 500 words

Business Process Modeling Approaches - Article Example Paul Harmon comes in to provide much simpler, quicker, less expensive yet equally beneficial ways of improving the performance of one’s business. Paul picks up from Rummler and Brache who introduced a very straight forward modeling approach (Harmon, 2003). They named this approach Process Mapping. The Process Mapping model was further developed to form the Unified Language Modeling and later into the Business Process Modeling Notation. Paul argues that these models involve the use of extra work and he tries to simplify them while at the same time ensuring that the end results will be equally worth it. He starts by saying that any business that wants to carry out a business process modeling needs to identify its current position, reasons for the remodeling as well as what it wants to achieve at the end of the process. In his book Business Process Change, Paul picks up on the Unified Modeling Language to describe and uses it to describe various business processes that may need remodeling if a business is to improve its efficiency. Here, Paul identifies different levels of business process from external processes, top-level processes down to the junior-level processes where roles have been assigned to various junior officers in the company. He says that it is important for every business level to be remodeled if the company wants the best results from the whole business modeling process (Harmon, 2003). Paul Harmon brings out various business modeling diagrams that are essential for a business to have. He introduces that ‘is diagrams’ which reflect the company’s current position, the ‘could diagrams’ which indicate the company’s targets and that ‘should diagrams’ which are a must attain target for the company. He recognizes the need for a business to integrate human activities and information technology (IT) activities in the modeling process for best results. According to Paul, any efficient

Advertisement Essay Example | Topics and Well Written Essays - 750 words

Advertisement - Essay Example The Argument The advertisement is arguing the point that with the new Nissan Dualis, one of the features being promoted as its focal point is its 360 ° view or the ability of the driver to be able to monitor his surroundings from the driver’s seat from a 360 ° perspective. The advertisement was therefore effective in providing a visual presentation of indicating how the 360 ° view could be depicted perfectly by positioning the female model in 12 strategic identical poses. The image thereby represents looking at strategic areas around the vehicle from complete circular points of view. The Target Audience The target audience that is perceived from the advertisement is female drivers, who would be more interested in being extra careful in monitoring the condition of the vehicle’s situation from a complete 360 ° view. More specifically, it is directed to female and young adult professional drivers, as depicted from the model that they used in the advertisement. The female model is perceived to be in her early 20s and her manner of carrying herself through the outfit she wears (white crisp blouse over a blue tight jeans and with a red belt) is indicative of her being in a carefree lifestyle, possibly in an exciting career. But of course, the advertisement could also be directed to all automobile drivers who are interested in owning the Nissan Dualis, with this 360 ° Around View Monitor. Rhetorical Principles Employed The rhetorical principles that were employed are a collaboration of logos (logic), pathos (emotion) and ethos (character). The rhetorical principle of logos was evident from the effective display of visual representation that captured the message of 360 ° view from the strategic positions of the female model. Likewise, the captions below the focal images with states: â€Å"PARK PERFECTLY WITH A 360 ° VIEW. The 360 ° Around View Monitor. Nissan Innovation that excites† (Best Ads) uses logical and emotional appeal thro ugh provision of factual information, in conjunction with the use of words that entices the emotion (excites). Finally, the rhetorical principle of ethos (character) is relayed through inclusion of Nissan’s logo and brand name, as well as the name of the vehicle being advertised, situated effectively at the upper left hand corner and colored in bold red to stand out against the immaculately white background with very faint shades of possibly light gray around the borders. The brand name, in itself, solicits character and credibility as one of the trusted brands in cars, known worldwide. Conformity to Advertisement Theories and Strategies As learned from the course modules, it is relevant that advertisements contain an effective interplay of both visual and verbal contents to make the advertisement effective. As such, this particular concept is appropriately applied in the Nissan Dualis: Park Perfectly ad which was proven to have used exemplary visual contents and assisted wit h verbal contents. But, as contented by Rossiter, â€Å"visual content warrants relatively more advertiser attention than verbal content† (101). From the impact that the visual content creates to the target audience, it is therefore supported that this concept is validated. One therefore agrees that the ability of the creator of the advertisement to design a visual image that would effectively relay the message that is intended, in a creative and innovative fashion, significantly assists in considering the advertisment a success – especially when the advertisement effort created that action intented by the organization;

Miss.Independent Essay Example for Free

Miss.Independent Essay Abstract We survey the phenomenon of the growth of ? rms drawing on literature from economics, management, and sociology. We begin with a review of empirical ‘stylised facts’ before discussing theoretical contributions. Firm growth is characterized by a predominant stochastic element, making it di? cult to predict. Indeed, previous empirical research into the determinants of ? rm growth has had a limited success. We also observe that theoretical propositions concerning the growth of ? rms are often amiss. We conclude that progress in this area requires solid empirical work, perhaps making use of novel statistical techniques. JEL codes: L25, L11 Keywords: Firm Growth, Size Distribution, Growth Rates Distribution, Gibrat’s Law, Theory of the Firm, Diversi? cation, ‘Stages of Growth’ models. ? I thank Giulio Bottazzi, Giovanni Dosi, Ha? da El-Younsi, Jacques Mairesse, Bernard Paulr? , Rekha Rao, e Angelo Secchi and Ulrich Witt for helpful comments. Nevertheless, I am solely responsible for any errors or confusion that may remain. This version: May 2007 †  Corresponding Author : Alex Coad, Max Planck Institute of Economics, Evolutionary Economics Group, Kahlaische Strasse 10, D-07745 Jena, Germany. Phone: +49 3641 686822. Fax : +49 3641 686868. E-mail : [emailprotected] mpg. de 1 #0703 Contents 1 Introduction 3 2 Empirical evidence on ? rm growth 2. 1 Size and growth rates distributions . . . . 2. 1. 1 Size distributions . . . . . . . . . . 2. 1. 2 Growth rates distributions . . . . . 2. 2 Gibrat’s Law . . . . . . . . . . . . . . . . 2. 2. 1 Gibrat’s model . . . . . . . . . . . 2. 2. 2 Firm size and average growth . . . 2. 2. 3 Firm size and growth rate variance 2. 2. 4 Autocorrelation of growth rates . . 2. 3 Other determinants of ? rm growth . . . . 2. 3. 1 Age . . . . . . . . . . . . . . . . . 2. 3. 2 Innovation . . . . . . . . . . . . . . 2. 3. 3 Financial performance . . . . . . . 2. 3. 4 Relative productivity . . . . . . . . 2. 3. 5 Other ? rm-speci? c factors . . . . . 2. 3. 6 Industry-speci? c factors . . . . . . 2. 3. 7 Macroeconomic factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4 4 5 9 9 11 14 15 18 18 19 23 25 26 28 29 3 Theoretical contributions 3. 1 Neoclassical foundations – growth towards an ‘optimal size’ . . . . 3. 2 Penrose’s ‘Theory of the Growth of the Firm’ . . . . . . . . . . . 3. 3 Marris and ‘managerialism’ . . . . . . . . . . . . . . . . . . . . . 3. 4 Evolutionary Economics and the principle of ‘growth of the ? tter’ 3. 5 Population ecology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 31 32 34 35 38 . . . . . . . 39 39 40 43 44 45 46 49 5 Growth of small and large ? rms 5. 1 Di? erences in growth patterns for small and large ? rms . . . . . . . . . . . . . 5. 2 Modelling the ‘stages of growth’ . . . . . . . . . . . . . . . . . . . . . . . . . . 51 51 53 6 Conclusion 56 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Growth strategies 4. 1 Attitudes to growth . . . . . . . . . . . . . . . . . . . 4. 1. 1 The desirability of growth . . . . . . . . . . . 4. 1. 2 Is growth intentional or does it ‘just happen’ ? 4. 2 Growth strategies – replication or diversi? cation . . . 4. 2. 1 Growth by replication . . . . . . . . . . . . . 4. 2. 2 Growth by diversi? cation . . . . . . . . . . . . 4. 3 Internal growth vs growth by acquisition . . . . . . . 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . #0703 1 Introduction The aim of this survey is to provide an overview of research into the growth of ? rms, while also highlighting areas in need of further research. It is a multidisciplinary survey, drawing on contributions made in economics, management and also sociology. There are many di? erent measures of ? rm size, some of the more usual indicators being employment, total sales, value-added, total assets, or total pro? ts; and some of the less conventional ones such as ‘acres of land’ or ‘head of cattle’ (Weiss, 1998). In this survey we consider growth in terms of a range of indicators, although we devote little attention to the growth of pro? ts (this latter being more of a ? nancial than an economic variable). There are also di? erent ways of measuring growth rates. Some authors (such as Delmar et al. , 2003) make the distinction between relative growth (i. e. the growth rate in percentage terms) and absolute growth (usually measured in the absolute increase in numbers of employees). In this vein, we can mention the ‘Birch index’ which is a weighted average of both relative and absolute growth rates (this latter being taken into account to emphasize that large ? rms, due to their large size, have the potential to create many jobs). This survey focuses on relative growth rates only. Furthermore, in our discussion of the processes of expansion we emphasize positive growth and not so much negative growth. 1 In true Simonian style,2 we begin with some empirical insights in Section 2, considering ? rst the distributions of size and growth rates, and moving on to look for determinants of growth rates. We then present some theories of ? rm growth and evaluate their performance in explaining the stylised facts that emerge from empirical work (Section 3). In Section 4 we consider the demand and supply sides of growth by discussing the attitudes of ? rms towards growth opportunities as well as investigating the processes by which ? rms actually grow (growth by ‘more of the same’, growth by diversi? cation, growth by acquisition). In Section 5 we examine the di? erences between the growth of small and large ? rms in greater depth. We also review the ‘stages of growth’ models. Section 6 concludes. 2 Empirical evidence on ? rm growth To begin with, we take a non-parametric look at the distributions of ? rm size and growth rates, before moving on to results from regressions that investigate the determinants of growth rates. 1 2 For an introduction to organizational decline, see Whetten (1987). See in particular Simon (1968). 3 #0703 2. 1 Size and growth rates distributions A suitable starting point for studies into industrial structure and dynamics is the ?rm size distribution. In fact, it was by contemplating the empirical size distribution that Robert Gibrat (1931) proposed the well-known ‘Law of Proportionate E? ect’ (also known as ‘Gibrat’s law’). We also discuss the results of research into the growth rates distribution. The regularity that ? rm growth rates are approximately exponentially distributed was discovered only recently, but o? ers unique insights into the growth patterns of ? rms. 2. 1. 1 Size distributions The observation that the ? rm-size distribution is positively skewed proved to be a useful point of entry for research into the structure of industries. (See Figures 1 and 2 for some examples of aggregate ? rm size distributions. ) Robert Gibrat (1931) considered the size of French ? rms in terms of employees and concluded that the lognormal distribution was a valid heuristic. Hart and Prais (1956) presented further evidence on the size distribution, using data on quoted UK ? rms, and also concluded in favour of a lognormal model. The lognormal distribution, however, can be viewed as just one of several candidate skew distributions. Although Simon and Bonini (1958) maintained that the â€Å"lognormal generally ? ts quite well† (1958: p611), they preferred to consider the lognormal distribution as a special case in the wider family of ‘Yule’ distributions. The advantage of the Yule family of distributions was that the phenomenon of arrival of new ? rms could be incorporated into the model. Steindl (1965) applied Austrian data to his analysis of the ? rm size distribution, and preferred the Pareto distribution to the lognormal on account of its superior performance in describing the upper tail of the distribution. Similarly, Ijiri and Simon (1964, 1971, 1974) apply the Pareto distribution to analyse the size distribution oflarge US ? rms. E? orts have been made to discriminate between the various candidate skew distributions. One problem with the Pareto distribution is that the empirical density has many more middlesized ? rms and fewer very large ? rms than would be theoretically predicted (Vining, 1976). Other research on the lognormal distribution has shown that the upper tail of the empirical size distribution of ? rms is too thin relative to the lognormal (Stanley et al. , 1995). Quandt (1966) compares the performance of the lognormal and three versions of the Pareto distribution, using data disaggregated according to industry. He reports the superiority of the lognormal over the three types of Pareto distribution, although each of the distributions produces a best-? t for at least one sample. Furthermore, it may be that some industries (e. g. the footwear industry) are not ? tted well by any distribution. More generally, Quandt’s results on disaggregated data lead us to suspect that the regu4 #0703 larities of the ? rm-size distribution observed at the aggregate level do not hold with sectoral disaggregation. Silberman (1967) also ? nds signi? cant departures from lognormality in his analysis of 90 four-digit SIC sectors. It has been suggested that, while the ? rm size distribution has a smooth regular shape at the aggregate level, this may merely be due to a statistical aggregation e? ect rather than a phenomenon bearing any deeper economic meaning (Dosi et al, 1995; Dosi, 2007). Empirical results lend support to these conjectures by showing that the regular unimodal ? rm size distributions observed at the aggregate level can be decomposed into much ‘messier’ distributions at the industry level, some of which are visibly multimodal (Bottazzi and Secchi, 2003; Bottazzi et al. , 2005). For example, Bottazzi and Secchi (2005) present evidence of signi? cant bimodality in the ? rm size distribution of the worldwide pharmaceutical industry, and relate this to a cleavage between the industry leaders and fringe competitors. Other work on the ? rm-size distribution has focused on the evolution of the shape of the distribution over time. It would appear that the initial size distribution for new ? rms is particularly right-skewed, although the log-size distribution tends to become more symmetric as time goes by. This is consistent with observations that small young ? rms grow faster than their larger counterparts. As a result, it has been suggested that the log-normal can be seen as a kind of ‘limit distribution’ to which a given cohort of ? rms will eventually converge. Lotti and Santarelli (2001) present support for this hypothesis by tracking cohorts of new ? rms in several sectors of Italian manufacturing. Cabral and Mata (2003) ? nd similar results in their analysis of cohorts of new Portuguese ? rms. However, Cabral and Mata interpret their results by referring to ? nancial constraints that restrict the scale of operations for new ? rms, but become less binding over time, thus allowing these small ?rms to grow relatively rapidly and reach their preferred size. They also argue that selection does not have a strong e? ect on the evolution of market structure. Although the skewed nature of the ? rm size distribution is a robust ? nding, there may be some other features of this distribution that are speci? c to countries. Table 1, taken from Bartelsman et al. (2005), highlights some di? erences in the structure of industries across countries. Among other things, one observes that large ? rms account for a considerable share of French industry, whereas in Italy ? rms tend to be much smaller on average. (These international di? erences cannot simply be attributed to di? erences in sectoral specialization across countries. ) 2. 1. 2 Growth rates distributions It has long been known that the distribution of ? rm growth rates is fat-tailed. In an early contribution, Ashton (1926) considers the growth patterns of British textile ? rms and observes 5 US 86. 7 69. 9 87. 9 16. 6 5. 8 Western Germany 87. 9 77. 9 90. 2 23. 6 11. 3 78. 6 73. 6 78. 8 13. 9 17. 0 France Italy 93. 1 87. 5 96. 5 34. 4 30. 3 74. 9 8. 3 UK Canada Denmark 90. 0 74. 0 90. 8 30. 2 16. 1 92. 6 84. 8 94. 5 25. 8 13. 0 Finland Netherlands 95. 8 86. 7 96. 8 31. 2 16. 9 86. 3 70. 5 92. 8 27. 7 15. 7 Portugal Source: Bartelsman et al. (2005: Tables 2 and 3). Notes: the columns labelled ‘share of employment’ refer to the employment share 6 26. 4 17. 0 33. 5 10. 5 12. 7 13. 3 13. 0 6. 5 16. 8 Total economy 80. 3 39. 1 32. 1 15. 3 40. 7 40. 5 30. 4 27. 8 18. 3 31. 0 Manufacturing 21. 4 11. 5 35. 7 6. 8 12. 0 12. 7 9. 9 5. 3 11. 4 Business services Ave. No. Employees per ? rm of ? rms with fewer than 20 employees. 20. 6 33. 8 12. 1 46. 3 33. 4 33. 0 41. 9 39. 8 Business services Total economy Manufacturing Share of employment (%) Business services Total economy. Manufacturing Absolute number (%) Table 1: The importance of small ? rms (i. e. ?rms with fewer than 20 employees) across broad sectors and countries, 1989-94 #0703 #0703 1 Pr 1998 2000 2002 0. 1 0. 01 0. 001 1e-04 -4 -2 0 s 2 4 6 Figure 1: Kernel estimates of the density of ?rm size (total sales) in 1998, 2000 and 2002, for French manufacturing ? rms with more than 20 employees. Source: Bottazzi et al. , 2005. Figure 2: Probability density function of the sizes of US manufacturing ? rms in 1997. Source: Axtell, 2001. that â€Å"In their growth they obey no one law. A few apparently undergo a steady expansion.. . With others, increase in size takes place by a sudden leap† (Ashton 1926: 572-573). Little (1962) investigates the distribution of growth rates, and also ? nds that the distribution is fat-tailed. Similarly, Geroski and Gugler (2004) compare the distribution of growth rates to the normal case and comment on the fat-tailed nature of the empirical density. Recent empirical research, from an ‘econophysics’ background, has discovered that the distribution of ? rm growth rates closely follows the parametric form of the Laplace density. Using the Compustat database of US manufacturing ? rms, Stanley et al. (1996) observe a ‘tent-shaped’ distribution on log-log plots that corresponds to the symmetric exponential, or Laplace distribution (see also Amaral et al. (1997) and Lee et al. (1998)). The quality of the ? t of the empirical distribution to the Laplace density is quite remarkable. The Laplace distribution is also found to be a rather useful representation when considering growth rates of ? rms in the worldwide pharmaceutical industry (Bottazzi et al. , 2001). Giulio Bottazzi and coauthors extend these ? ndings by considering the Laplace density in the wider context of the family of Subbotin distributions (beginning with Bottazzi et al., 2002). They ? nd that, for the Compustat database, the Laplace is indeed a suitable distribution for modelling ? rm growth rates, at both aggregate and disaggregated levels of analysis (Bottazzi and Secchi 2003a). The exponential nature of the distribution of growth rates also holds for other databases, such as Italian manufacturing (Bottazzi et al. (2007)). In addition, the exponential distribution appears to hold across a variety of ? rm growth indicators, such as Sales growth, employment growth or Value Added growth (Bottazzi et al. , 2007). The growth rates of French manufacturing ? rms have also been studied, and roughly speaking a similar shape was observed, although it must be said that the empirical density was noticeably fatter-tailed than the Laplace (see Bottazzi et al. , 2005). 3 3 The observed subbotin b parameter (the ‘shape’ parameter) is signi? cantly lower than the Laplace value of 1. This highlights the importance of following Bottazzi et al. (2002) and considering the Laplace as a special 7 #0703 1998 2000 2002 1998 2000 2002 1 prob. prob. 1 0. 1 0. 01 0. 1 0. 01 0. 001 0. 001 -3 -2 -1 0 1 2 -2 -1. 5 -1 conditional growth rate -0. 5 0 0. 5 1 1. 5 2 conditional growth rate. Figure 3: Distribution of sales growth rates of French manufacturing ? rms. Source: Bottazzi et al. , 2005. Figure 4: Distribution of employment growth rates of French manufacturing ? rms. Source: Coad, 2006b. Research into Danish manufacturing ? rms presents further evidence that the growth rate distribution is heavy-tailed, although it is suggested that the distribution for individual sectors may not be symmetric but right-skewed (Reichstein and Jensen (2005)). Generally speaking, however, it would appear that the shape of the growth rate distribution is more robust to disaggregation than the shape of the ?rm size distribution. In other words, whilst the smooth shape of the aggregate ? rm size distribution may be little more than a statistical aggregation e? ect, the ‘tent-shapes’ observed for the aggregate growth rate distribution are usually still visible even at disaggregated levels (Bottazzi and Secchi, 2003a; Bottazzi et al. , 2005). This means that extreme growth events can be expected to occur relatively frequently, and make a disproportionately large contribution to the evolution of industries. Figures 3 and 4 show plots of the distribution of sales and employment growth rates for French manufacturing ?rms with over 20 employees. Although research suggests that both the size distribution and the growth rate distribution are relatively stable over time, it should be noted that there is great persistence in ? rm size but much less persistence in growth rates on average (more on growth rate persistence is presented in Section 2. 2. 4). As a result, it is of interest to investigate how the moments of the growth rates distribution change over the business cycle. Indeed, several studies have focused on these issues and some preliminary results can be mentioned here. It has been suggested that the variance of growth rates changes over time for the employment growth of large US ? rms (Hall, 1987) and that this variance is procyclical in the case of growth of assets (Geroski et al. , 2003). This is consistent with the hypothesis that ? rms have a lot of discretion in their growth rates of assets during booms but face stricter discipline during recessions. Higson et al. (2002, 2004) consider the evolution of the ? rst four moments of distributions of the growth of sales, for large US and UK ?rms over periods of 30 years or more. They observe that higher moments of the distribution of sales growth rates have signi? cant cyclical patterns. In case in the Subbotin family of distributions. 8 #0703 particular, evidence from both US and UK ? rms suggests that the variance and skewness are countercyclical, whereas the kurtosis is pro-cyclical. Higson et al. (2002: 1551) explain the counter-cyclical movements in skewness in these words: â€Å"The central mass of the growth rate distribution responds more strongly to the aggregate shock than the tails. So a negative shock moves the central mass closer to the left of the distribution leaving the right tail behind and generates positive skewness. A positive shock shifts the central mass to the right, closer to the group of rapidly growing ? rms and away from the group of declining ? rms. So negative skewness results. † The procyclical nature of kurtosis (despite their puzzling ? nding of countercyclical variance) emphasizes that economic downturns change the shape of the growth rate distribution by reducing a key parameter of the ‘spread’ or ‘variation’ between ? rms. 2. 2 Gibrat’s Law. Gibrat’s law continues to receive a huge amount of attention in the empirical industrial organization literature, more than 75 years after Gibrat’s (1931) seminal publication. We begin by presenting the ‘Law’, and then review some of the related empirical literature. We do not attempt to provide an exhaustive survey of the literature on Gibrat’s law, because the number of relevant studies is indeed very large. (For other reviews of empirical tests of Gibrat’s Law, the reader is referred to the survey by Lotti et al (2003); for a survey of how Gibrat’s law holds for the services sector see Audretsch et al. (2004). ) Instead, we try to provide an overview of the essential results. We investigate how expected growth rates and growth rate variance are in? uenced by ? rm size, and also investigate the possible existence of patterns of serial correlation in ? rm growth. 2. 2. 1 Gibrat’s model Robert Gibrat’s (1931) theory of a ‘law of proportionate e? ect’ was hatched when he observed that the distribution of French manufacturing establishments followed a skew distribution that resembled the lognormal. Gibrat considered the emergence of the ?rm-size distribution as an outcome or explanandum and wanted to see which underlying growth process could be responsible for generating it. In its simplest form, Gibrat’s law maintains that the expected growth rate of a given ? rm is independent of its size at the beginning of the period examined. Alternatively, as Mans? eld (1962: 1030) puts it, â€Å"the probability of a given proportionate change in size during a speci? ed 9 #0703 period is the same for all ? rms in a given industry – regardless of their size at the beginning of the period. † More formally, we can explain the growth of ? rms in the following framework. Let xt be the size of a ? rm at time t, and let ? t be random variable representing an idiosyncratic, multiplicative growth shock over the period t ? 1 to t. We have xt ? xt? 1 = ? t xt? 1 (1) xt = (1 + ? t )xt? 1 = x0 (1 + ? 1 )(1 + ? 2 ) . . . (1 + ? t ) (2) which can be developed to obtain It is then possible to take logarithms in order to approximate log(1 + ? t ) by ? t to obtain4 t log(xt ) ? log(x0 ) + ? 1 + ? 2 + . . . + ? t = log(x0 ) + ?s (3) s=1 In the limit, as t becomes large, the log(x0 ) term will become insigni? cant, and we obtain t log(xt ) ? ?s (4) s=1 In this way, a ? rm’s size at time t can be explained purely in terms of its idiosyncratic history of multiplicative shocks. If we further assume that all ? rms in an industry are independent realizations of i. i. d. normally distributed growth shocks, then this stochastic process leads to the emergence of a lognormal ? rm size distribution. There are of course several serious limitations to such a simple vision of industrial dynamics. We have already seen that the distribution of growth rates is not normally distributed, but instead resembles the Laplace or ‘symmetric exponential’. Furthermore, contrary to results implied by Gibrat’s model, it is not reasonable to suppose that the variance of ? rm size tends to in? nity (Kalecki, 1945). In addition, we do not observe the secular and unlimited increase in industrial concentration that would be predicted by Gibrat’s law (Caves, 1998). Whilst a ‘weak’ version of Gibrat’s law merely supposes that expected growth rate is independent of ?rm size, stronger versions of Gibrat’s law imply a range of other issues. For example, Chesher (1979) rejects Gibrat’s law due to the existence of an autocorrelation structure in the growth shocks. Bottazzi and Secchi (2006a) reject Gibrat’s law on the basis of a negative relationship between growth rate variance and ? rm size. Reichstein and Jensen (2005) reject Gibrat’s law 4 This logarithmic approximation is only justi? ed if ? t is ‘small’ enough (i. e. close to zero), which can be reasonably assumed by taking a short time period (Sutton, 1997). 10 #0703after observing that the annual growth rate distribution is not normally distributed. 2. 2. 2 Firm size and average growth Although Gibrat’s (1931) seminal book did not provoke much of an immediate reaction, in recent decades it has spawned a ? ood of empirical work. Nowadays, Gibrat’s ‘Law of Proportionate E? ect’ constitutes a benchmark model for a broad range of investigations into industrial dynamics. Another possible reason for the popularity of research into Gibrat’s law, one could suggest quite cynically, is that it is a relatively easy paper to write. First of all, it has been argued that there is a minimalistic theoretical background behind the process (because growth is assumed to be purely random). Then, all that needs to be done is to take the IO economist’s ‘favourite’ variable (i. e. ?rm size, a variable which is easily observable and readily available) and regress the di? erence on the lagged level. In addition, few control variables are required beyond industry dummies and year dummies, because growth rates are characteristically random. Empirical investigations of Gibrat’s law rely on estimation of equations of the type: log(xt ) = ?+ ? log(xt? 1 ) + (5) where a ? rm’s ‘size’ is represented by xt , ? is a constant term (industry-wide growth trend) and is a residual error. Research into Gibrat’s law focuses on the coe? cient ?. If ? rm growth is independent of size, then ? takes the value of unity. If ? is smaller than one, then smaller ? rms grow faster than their larger counterparts, and we can speak of ‘regression to the mean’. Conversely, if ? is larger than one, then larger ? rms grow relatively rapidly and there is a tendency to concentration and monopoly. A signi?cant early contribution was made by Edwin Mans? eld’s (1962) study of the US steel, petroleum, and rubber tire industries. In particular interest here is what Mans? eld identi? ed as three di? erent renditions of Gibrat’s law. According to the ? rst, Gibrat-type regressions consist of both surviving and exiting ? rms and attribute a growth rate of -100% to exiting ? rms. However, one caveat of this approach is that smaller ? rms have a higher exit hazard which may obfuscate the relationship between size and growth. The second version, on the other hand, considers only those ?rms that survive. Research along these lines has typically shown that smaller ? rms have higher expected growth rates than larger ? rms. The third version considers only those large surviving ? rms that are already larger than the industry Minimum E? cient Scale of production (with exiting ? rms often being excluded from the analysis). Generally speaking, empirical analysis corresponding to this third approach suggests that growth rates are more or less independent from ? rm size, which lends support to Gibrat’s law. 11 #0703 The early studies focused on large ? rms only, presumably partly due to reasons of data availability. A series of papers analyzing UK manufacturing ? rms found a value of ? greater than unity, which would indicate a tendency for larger ? rms to have higher percentage growth rates (Hart (1962), Samuels (1965), Prais (1974), Singh and Whittington (1975)). However, the majority of subsequent studies using more recent datasets have found values of ? slightly lower than unity, which implies that, on average, small ? rms seem to grow faster than larger ? rms. This result is frequently labelled ‘reversion to the mean size’ or ‘mean-reversion’. 5 Among a large and growing body of research that reports a negative relationship between size and growth, we can mention here the work by Kumar (1985) and Dunne and Hughes (1994) for quoted UK manufacturing ? rms, Hall (1987), Amirkhalkhali and Mukhopadhyay (1993) and Bottazzi and Secchi (2003) for quoted US manufacturing ? rms (see also Evans (1987a, 1987b) for US manufacturing ? rms of a somewhat smaller size), Gabe and Kraybill (2002) for establishments in Ohio, and Goddard et al. (2002) for quoted Japanese manufacturing ? rms. Studies focusing on small businesses have also found a negative relationship between ? rm size and expected growth – see for example Yasuda (2005) for Japanese manufacturing ? rms, Calvo (2006) for Spanish manufacturing, McPherson (1996) for Southern African micro businesses, and Wagner (1992) and Almus and Nerlinger (2000) for German manufacturing. Dunne et al. (1989) analyse plant-level data (as opposed to ? rm-level data) and also observe that growth rates decline along size classes. Research into Gibrat’s law using data for speci? c sectors also ? nds that small ? rms grow relatively faster (see e. g. Barron et al. (1994) for New York credit unions, Weiss (1998) for Austrian farms, Liu et al. (1999) for Taiwanese electronics plants, and Bottazzi and Secchi (2005) for an analysis of the worldwide pharmaceutical sector). Indeed, there is a lot of evidence that a slight negative dependence of growth rate on size is present at various levels of industrial aggregation. Although most empirical investigations into Gibrat’s law consider only the manufacturing sector, some have focused on the services sector. The results, however, are often qualitatively similar – there appears to be a negative relationship between size and expected growth rate for services too (see Variyam and Kraybill (1992), Johnson et al. (1999)) Nevertheless, it should be mentioned that in some cases a weak version of Gibrat’s law cannot be convincingly rejected, since there appears to be no signi? cant relationship between expected growth rate and size (see the analyses provided by Bottazzi et al. (2005) for French manufacturing ? rms, Droucopoulos (1983) for the world’s largest ? rms, Hardwick and Adams (2002) for UK Life Insurance companies, and Audretsch et al. (2004) for small-scale Dutch services). Notwithstanding these latter studies, however, we acknowledge that in most cases a negative relationship between ? rm size and growth is observed. Indeed, 5 We should be aware, however, that ‘mean-reversion’ does not imply that ? rms are converging to anything resembling a common steady-state size, even within narrowly-de? ned industries (see in particular the empirical work by Geroski et al. (2003) and Ce? s et al. (2006)). 12 #0703 it is quite common for theoretically-minded authors to consider this to be a ‘stylised fact’ for the purposes of constructing and validating economic models (see for example Cooley and Quadrini (2001), Gomes (2001) and Clementi and Hopenhayn (2006)). Furthermore, John Sutton refers to this negative dependence of growth on size as a ‘statistical regularity’ in his revered survey of Gibrat’s law (Sutton, 1997: 46). A number of researchers maintain that Gibrat’s law does hold for ? rms above a certain size threshold. This corresponds to acceptance of Gibrat’s law according to Mans? eld’s third rendition, although ‘mean reversion’ leads us to reject Gibrat’s Law as described in Mans? eld’s second rendition. Mowery (1983), for example, analyzes two samples of ? rms, one of which contains small ? rms while the other contains large ? rms. Gibrat’s law is seen to hold in the latter sample, whereas mean reversion is observed in the former. Hart and Oulton (1996) consider a large sample of UK ? rms and ? nd that, whilst mean reversion is observed in the pooled data, a decomposition of the sample according to size classes reveals essentially no relation between size and growth for the larger ? rms. Lotti et al. (2003) follow a cohort of new Italian startups and ? nd that, although smaller ? rms initially grow faster, it becomes more di? cult to reject the independence of size and growth as time passes. Similarly, results reported by Becchetti and Trovato (2002) for Italian manufacturing ? rms, Geroski and Gugler (2004) for large European ? rms and Ce? s et al. (2006) for the worldwide pharmaceutical industry also ? nd that the growth of large ? rms is independent of their size, although including smaller ? rms in the analysis introduces a dependence of growth on size. It is of interest to remark that Caves (1998) concludes his survey of industrial dynamics with the ‘substantive conclusion’ that Gibrat’s law holds for ? rms above a certain size threshold, whilst for smaller ? rms growth rates decrease with size. Concern about econometric issues has often been raised. Sample selection bias, or ‘sample attrition’, is one of the main problems, because smaller ? rms have a higher probability of exit. Failure to account for the fact that exit hazards decrease with size may lead to underestimation of the regression coe? cient (i. e. ?). Hall (1987) was among the ? rst to tackle the problem of sample selection, using a Tobit model.