Transportation Deployment Casebook/Automobile Safety
The invention of the automobile in the late 1800s was a breakthrough in the world of transportation. It allowed people the option to get where they wanted to go quicker than using a horse and carriage. In its early stages, cars were very expensive and it wasn’t until 1908 when Henry Ford developed a way to make cars using assembly lines that cars were able to be sold much cheaper than they had been previously. Since this time, automobile technology has gone places Henry Ford probably never saw coming. While technology has led to cars being built to higher safety standards, motor vehicle fatalities continue to occur as they did in the early days of the automobile. By looking at the life cycle of the automobile, as well as the amount of motor vehicle related fatalities that have occurred each year since 1899, the periods of birthing, growth, maturity and decline can be found for this mode of transportation. This provides an understanding of how technological advances and production of automobiles has either helped or hindered the safety of this mode since its creation.
The number of motor vehicle fatalities in the United States based on historical NHTSA and FHWA data was obtained and is shown in Table 1. This data is plotted along with S-curves used to estimate the periods of birthing, growth, maturity and decline. In this case, the data was broken up into two sections, the first being the number of fatalities from 1899 to 1962 as this represented the periods of birthing, growth and maturity. Another phase representing decline was seen between 1963 and 2009. The plot representing the number of motor vehicle fatalities between 1899 to 1962 can be seen in Figure 1.
The data was then used to estimate a three-parameter logistic function of the form:
S(t) = K/[1+exp(-b(t-to)] , where S(t) is the predicted number of fatalities.
Here, K, is the saturation status level. Since the data has already entered a phase of decline, K, is simply the highest fatality rate. This occurred in 1962 when the fatality rate was 39,980. A K value of 39,900 was used as it gave a better fit of the curve than using a K value of 39,980. Once a K value was determined, a calculation was done in preparation for performing the regression of the data. This calculation was used to estimate the dependent variable and was of the form:
Y = LN(Fatalities/(K - Fatalities)), where “Fatalities” is the number of fatalities from the data.
Next, a regression was performed using the “data analysis” tool in Microsoft Excel to help assess the accuracy of the fit of the predicted model to the actual data. The results of this analysis are shown in Tables 2, 3, and 4.
|Adjusted R Square||0.811499|
This analysis gives the intercept of the predicted model. In this case, the intercept was -284.6. The analysis also gives an estimate of the coefficient, b, which is used in the equation to predict the number of fatalities. For the time period of 1899 to 1962, b, was estimated to be .14736.
An estimate of the inflection time, to, or the year in which ½ K was reached was also needed. This was found by the following equation:
to = Intercept / -b
In this case, to, was estimated to be 1931.46.
Once all the variables were found to solve for S(t), predicted fatality rates could be determined for each year between 1899 and 1962. The resulting data is plotted in red in Figure 1. It forms an S-curve that fits the actual data as accurately as possible. The accuracy is based on the statistical information presented in Tables 2, 3, and 4. A K value of 39,900 provided the highest R-squared value of 0.814491. Typically, the closer an R-squared value is to 1, the more accurate the model represents the data. In this case, there are most likely outliers in the data that affect the R-squared value. It can be seen that the actual data itself does not perfectly follow an S-curve shape, so clearly, modeling an S-curve will not perfectly overlap the data. In this case, an R-squared value of .814491 is probably as good as one would expect given the data. From Table 4, it can be seen that the t-statistics were higher than 2, which means the results were statistically significant at the 95% confidence interval. Overall, this model seems to reflect the actual data.
Now that the results are known, the predicted model can be used to estimate the phases of birth, growth and maturity. From the availability of the data, the birth is shown to be in 1899, which is the first instance of fatality rates being recorded in this analysis. Since to was found to be 1931, this means that there was a period of growth from 1899 to 1931. The highest K value was found in 1962, which means that from 1931 to 1962, there was still a period of growth. However, this growth was slower than before 1931. This slower growth led to the number of fatalities reaching a point of maturity in 1962.
These periods of increasing and decreasing fatality rates can be attributed to changes in technology as well as in the sales of automobiles. For instance, as more and more people began purchasing vehicles it would be expected that a higher number of fatalities exist due to the increased amount of vehicle traffic as well as simply having a higher population of motor vehicle owners. After 1908, when Henry Ford started using the assembly line to mass-produce the cars allowing them to be sold for less money, there was an increased number of people purchasing and traveling by motor vehicle. This helps explain the phase of growth in motor vehicle fatalities. The 1930s began a phase in which safety started to become a focus in car manufacturing. The use of seatbelts was being advocated in the 1930s along with the use of padded dashboards to assist in safety in the event of a crash. (Georgano 1992) Mercedes Benz patented the safety cage in the 1940s. (Car Safety Features n.d.) This added safety focus helped make cars safer to drive and probably contributed to the slower rate of fatalities between 1931 and 1962. However, even though the cars were being made safer, the drastically increasing number of drivers is what kept the number of fatalities large. From the data, it can be seen that motor vehicle fatalities reached its maturity in 1962.
The phase post-1962 saw an overall decline in the number of motor vehicle fatalities. The plot representing the number of motor vehicle fatalities between 1962 and 2009 can be seen in Figure 2.
A similar analysis involving fitting an S-curve to the data and finding a model of best-fit was done again for this phase of the motor vehicle fatality rates. The results of this analyis are shown in Tables 5, 6, and 7. In this case, K, was determined from the plot and after testing different values of K, the line of best fit occurred when K equaled 55,000.
|Adjusted R Square||0.46955|
This analysis gives the intercept of the predicted model. In this case, the intercept was 96.008. The analysis also gives an estimate of the coefficient, b, which is used in the equation to predict the number of fatalities. For the time period of 1962 to 2009, b, was estimated to be -.047487.
An estimate of the inflection time, to, or the year in which ½ K was reached was also needed. This was found by the following equation:
to = Intercept / -b
In this case, to¬, was estimated to be 2021.77.
Once all the variables were found, S(t), or predicted fatality rates could be determined for each year between 1962 and 2009. The resulting data is plotted in red in Figure 2. It forms an S-curve that fits the actual data as accurately as possible. The accuracy is based on the statistical information presented in Tables 5, 6, and 7. A K value of 55,000 provided the highest R-squared value of 0.48108. Typically, the closer an R-squared value is to 1, the more accurate the model represents the data. In this case, there are so many twists and turns in the data, that trying to fit an S-curve just doesn’t match up that well and therefore, the R-squared value is affected. In this case, an R-squared value of .48108 is probably as good as one would expect given the data. There are many reasons for the non-linearity or constant declining trend in the actual data including changes to driver safety and changes in motor vehicle technology which created periods of increasing and decreasing fatality numbers within this overall phase of motor vehicle fatality decline.
Throughout the 1960s changes were being made and technology was improving to make cars safer to drive. One such change was the new standard in the United States that windshields had to have a deformable polymer layer so that in the event of a crash, a person riding in the vehicle would not go sailing through the windshield and be cut by the glass. The 1980s saw a drastic increase in car manufacturers using airbags even though they were invented in 1952. (Car Safety Features n.d.) These added safety features as well as cars being made with lighter weight materials is what contributed to the decline in fatal accidents in the U.S.
Policy changes since 1962 also affected the decline in the number of fatalities. New York passed the first law requiring seatbelts to be worn in 1984. This is now a law in every state in the U.S. Also, in various states, lowering the blood alcohol level and implementing harsher penalties for drunk driving has led to an increase in safety on the roads. These policy changes and advances in technology help explain the overall declining trend in motor vehicle related fatalities. While this trend is declining, it is known that accidents will continue to occur until technology advances a lot more, it is unrealistic to assume that the number of fatalities in a given year will ever be zero.
Now that the birth, growth, maturity and declining phases have been identified, it is worth taking a deeper look at this mode of transportation to learn more about the impact it has had on the transportation system and commuters in the United States since its creation in the late 1800s. The invention of the internal combustion engine in the early 1800s led to the invention of the automobile as it is known to consumers today. What is referred to as the “Otto cycle” is the four-cycle engine invented by Alphonse Bear de Rochas in 1862. This process brought gas into the cylinder, compressed it, combusted the compressed mixture and then exhausted it. Vehicles, which used this technology, ran on petroleum-based fuel, which is what we still use today. (Bottorff n.d.) Automobiles are now equipped with more safety features and are built more lighweight then when they were first invented. A car’s engine runs on a mixture of gasoline and air after getting an initial spark from the car’s battery which gets powered when a driver turns the key and ignites it. The car moves forward based on the energy it gets as the gas burns and moves the car forward. The car’s transmission passes all the energy from the engine to the four wheels. (Brain n.d.) A driver can steer the car in whichever direction they so choose adding to the convenience of this type of mode.
The Automobile as a New Mode
The main advantages to automobiles are that they offer passengers the option to commute from point A to point B on their own time. Unlike taking trains, planes or boats, lightrail systems or other modes, you can hop in a car at essentially anytime and get anywhere fast. Owning an automobile in todays society allows people to live in more suburban areas and still easily commute to a job in the city or at a distance farther then where they could easily get by walking, biking or taking the bus. Another advantage to the automobile is it allows people to easily haul items they might not be able to take on a bus or other mode of transportation. The main market for automobiles in the United States is primarily people over age 15 seeing as this is generally the age you can start driving. Since automobiles are expensive to purchase and maintain, a more reasonable market for automobiles would be working adults.
Before the Automobile
Prior to the advent of the automobile, people were primarily making shorter trips via horse drawn wagons and carriages. The limitations to the horse drawn carriage was that they could only travel up to 10 miles per day so it was a slow commute. (Economy 2010) Other options for transportation were boat, or train systems. The limitations to these other transportation systems were that they typically only traveled through large cities where they could connect to ports or in the event of the train, they could only travel to areas in which rail tracks had been previously built. These options didn’t offer that much convenience for taking shorter trips or travelling to smaller towns most likely not connected to train tracks.
In the beginning, cars were seen as a novelty item that only the rich could afford. It wasn’t until Henry Ford and his assembly line that cars were made for the masses and could be sold at much lower prices. (Davis 1976) Ford also built up his company by paying his employees higher wages so that they could buy a car from the company. Cars allowed people who had never been beyond their hometowns the option to get out and see the country. For people who had a car, it wasn’t even about the destination, it was about taking the drive itself as this was scene as something new and exciting that people had never done before.
In the early 1900s, the market for transportation was evolving as people were looking for more independent and faster ways to commute. People were looking for jobs outside their communities and were curious to explore. As people saw others driving cars, they quickly learned the ease of access having an automobile provided. Once cars became more affordable due to the assembly line style of production, more people were financially able to purchase an automobile.
Having an automobile stirred interest in new possibilities for people. For the first time, people were able to look for work outside their small towns. This meant they could have easier access to nearby towns to get supplies their town didn’t have. People could reach regional hospitals and attend schools in bigger towns so people were becoming more educated. Since people no longer needed to live close to railroad lines, small towns started to grow and develop.
Invention of the Automobile
As demand increased for automobiles, there was a technological shift in not only how cars were produced to provide more cars to be made each year, but technological advances led to better and more efficient vehicles being made. Attempts at automobiles using various technologies such as steam powered self propelled engines were being toyed with since the late 1700s to the mid 1800s. However, the very first car which more closely resembles the vehicles we know today was built in 1885 by Karl Benz who was an engineer from Germany. His design was a three wheeled machine with a single-cylinder engine. Not too long after this design was laid out, a four wheeled car was on the market. It wasn’t until 1891 however, that an engineer from France came up with the design to have the engine at the front which would drive the rear wheels through a clutch and a gearbox. (Bridgeman 2002) Once the main structure of the automobile was laid out, the next question became what type of engine would be used.
In 1885, Gottlieb Daimler and Wilhelm Maybach from Germany designed an effective carburetor. (Bridgeman 2002) This led to the creation of the first true gasoline engine and it is not that far off in design from those that power cars today. Another advancement in technology came in the early 1900s when the steering wheel was standardized. The pairing of early ideas for improvements of automobiles from engineers from across Europe was what led to the working model that Henry Ford later used. However, he added an assembly line building procedure which would expedite the process and allow for the cars to be sold at much cheaper prices because building the cars could be done by people not as highly skilled. Each person working could focus on one single area or part of the vehicle versus having someone try and build an entire car.
Shifts in the initial design of the automobile started to take place as inventors, engineers and designers learned from mistakes in the past and looked for ways to make improvements. Since the faster and more dependable cars were running on gasoline, the petroleum industry had to be advanced to keep up with the demand. Ways to produce gasoline and improvements in heat-tolerant oil lubricants were being studied as more and more vehicles on the road meant an increased demand in gasoline. The 1930s mixed existing technology with the automobile when car radios were installed in vehicles. Car heaters were also introduced in the 1930s which was a relief for people driving in colder climates. The number of cars on the road in 1910 was 458,000 as compared to 26,750,000 on the road in 1930. (Sass 2010) This meant improvements and advancements in engineering vehicles were being well received by the buying public.
The 1940s and 1950s brought about changes in safety of operating vehicles when turn signals and seatbelts were implemented. The 1950s also saw the use of gearboxes, disk brakes, electric windows, radial tires, and power steering. (Cars Auto and Car Information from the People History Site n.d.) As more technology was being used in cars, car prices increased. In the 1920s, a new car cost only $290. In 1947, the average cost of a new car was close to $1,300 and by 1955; the cost had risen to as much as $1,900. (Sass 2010) However, more people had jobs and were making more money than they had been in the recession in the 1920s so people were still buying vehicles even though they were costing more money.
Advancements continued, and in the 1970s four wheel drive and airbags were added. This was also the time a new breed of car manufacteurers from Japan entered the automobile market. At first, Japanese cars were built really cheap and were of poor quality. Japanese auto makers quickly learned that the buying public demanded higher standards in automobile production and they soon learned from their mistakes. Today, makers such as Toyota and Honda are among the world leaders in car sales and are leading the way in current advancements in hybrid technology. (Cars Auto and Car Information from the People History Site n.d.) This will continue to be an area of focus for the automobile industry as gasoline and petroleum are becoming a scarce commodity and are getting to be too expensive to be relied upon as the main source of fuel for the future.
After each oil crisis, the cost of petroleum increases and people shift their focus on ways to eliminate the use of petroleum in the industry. Over the last 20 years, these types of world events have led to cars becoming smaller and improvements in the fuel economy of vehicles have been demanded by the public. Overall, cars have become more fuel efficient. One of the main reasons is that engineers have been able to stop the engine from running when the car is stationary and the use of hybrid technology now allows the car batteries to charge while in motion. The use of hybrid technology is also greatly helping reduce the amount of pollution cars exert into the environment. All the changes that have happened in the past century with car engineering, including changes to the safety and comfort of operating vehicles has led to the designs we have today.
Early Market Development
The initial market niche for the automobile was primarily only the wealthy. This new mode of transportation at the time was considered to be the replacement for the horse drawn carriage but was not viewed as a primary means of transportation for everyone. Limited resources meant your average person could not afford an automobile. It wasn’t until Ford came out with his Model T, that the world saw its first economy car, or one which more people could afford and use as a reasonable mode for travel.
As people realized the speed and efficiency the automobile provided, they understood that they could get around the city faster with the use of the automobile. The automobile served existing transportation markets better in that it provided speed and convenience by allowing passengers the option to travel at much greater speeds than the horse drawn carriage provided. Early automobiles that didn’t have windshields meant a lot of dust and debris flying in passengers eyes. (Davis 1976) This type of problem led to the creation of a pavement industry. The advancement of automobiles was soon followed by the development of paved roads and road network systems as people quickly realized that driving cars on unpaved roads meant a really bumpy ride. Traveling on smoother roads was another way existing markets were better served.
There were many new markets which were also served due to the development of the automobile industry. People in smaller towns and communities who were using only horse drawn carriages were not afforded the chance to get out and explore connecting communities as it took too long to travel places with that mode. Having an automobile meant people could get out and see their country more than they ever could before. They could travel easier and farther than with horses. People could now vacation and camp because they could pack more items in their vehicles and get to locations farther away from their communities. The use of the automobile helped create other industries which made use of the automobile and thus assisted in market development. For instance, fast food industries developed with drive thrus geared towards servicing peole driving automobiles. In 1909, for the first time ever, an automobile hearse was used in a funeral procession. Before this time, horse-drawn carriages had always been used to carry the body of a person who had passed away. Another example was police and highway patrols using automobiles to respond to emergencies quicker than they had been able to previously. The market developed even more since towns began to grow and jobs opened up far from large cities. People could then commute to work via the automobile and not have to rely on only finding jobs in the cities.
Policy in the Birthing Phase
In order to really develop as a transportation mode that could service the masses, policy changes had to be put in place to aid in the organization of the automobile system. Some policies were carried over from previous transportation networks, however, because the automobile was so different from previous modes, a lot of policies had to be envisioned. One policy that was carried over from a former mode was the idea that cars would drive on the right or left side of the road. Earlier horse and carriage networks may not have had well defined rules for sharing the road as they may have even went off road, there was still some sense of organization on the road to avoid collisions. This same idea was carried over to automobile networks. However, more stringent protocols were required since these new motor vehicles were more dangerous than a horse and carriage. Likewise, road maps similar to maps that were established for railroad networks were developed for automobiles especially when more highway systems started to be developed. Highway systems were set up similar to roadway systems in that they were designed to connect major cities.
Many policies and agencies needed to be created to organize the automobile network. New laws were put in place to keep people safe on the roads. For instance, the first speed limit was put in place in Connecticut. In 1901, you could go no faster than 10 mph in cities, 15 mph in villages and 20 mph in rural areas in Connecticut. (Speed n.d.) This soon spread to other states implementing similar laws to keep drivers safe on the roads.
Agencies were created to help implement safety on the roads and deal with automobile related policy. In 1902, the American Automobile Association (AAA) was created. AAA was created in Chicago primarily because groups of motor clubs felt there was inadequate attention being paid to roads and highways suitable for automobiles. In 1905, AAA put out a serious of road maps so people could navigate their way around the country. (AAA n.d.) In 1936, it was AAA who published the first driver education program to teach high school students the rules of the road, however rules were in place since 1910 in the United States regarding needing a drivers license to operate a motor vehicle. The first licensing law for motor vehicles was implemented in New York and was initially applied to professional chauffeurs. It wasn’t until 1913 in New Jersey that all drivers were required to pass a mandatory exam before receiving a license. (New York Times 1913) AAA also began a pedestrian safety program with a grant from the Automotive Safety Foundation and in 1938, published a study to try and reduce the amount of pedestrian fatalities and injuries.
In addition to AAA, government organizations were developed such as the state Department of Transportation organizations who were responsible for implementing and maintaining roads and motor vehicle safety standards for each state. In addition, an extensive network of signs and traffic signals contributed to an intricate language that drivers quickly adapted to. Stop signs and red lights soon became signals that cars needed to stop. These types of rules of the road allowed for safer driving and kept some order on the crowded roads and highways. In relation to the plot produced in the beginning of this report, the birthing phase, or the start of motor vehicle related fatalities started almost simultaneously with the birth of the automobile. Early automobiles were built with no real safety features and heavy metals so when accidents occurred, there was little to protect passengers. Advancements in safety features and the use of lighter weight materials over the years has helped address these issues.
Growth of the Mode
The automobile industry has shown significant growth due to innovative technology and high demand by the public. This has been helped by both the private and public sectors. When automobile manufacturers run out of industry supported research and development, it is up to federal policies and investments to re-ignite the flame and inspire creative and innovative options that will ensure cars keep their competitive advantage over other modes of transportation.
Innovation in the automobile industry can arise from a few main sources. Automotive assemblers such as General Motors, Ford and Toyota can spark innovation from within. Firms may choose to support the auto industry with components and subsystems. (Klier and Sands 2010) Universities as well as public and private research can help accelerate the development of technology as well. The problem with some of these sources is their interest in the overall industry. For example, a firm might focus on the needs of the market and build automobiles that would sell in large quantities at high prices so that they would make a lot of money. This is not in the best interest of the industry however, as it is more important to invest in new technologies that will help mold automobiles into something newer and better instead of something shinier or bigger.
The private sector of the automobile industry extends far beyond the automobile makers themselves. Private sector efforts encompass an auto makers entire supply chain. (Klier and Sands 2010) In order to overcome some of the externalities associated with the private sector, the government is often needed to step in and implement policies that will better benefit the public. One of the government policies that has been adopted includes research on more fuel efficient vehicles.
Sometimes however, federal policy and programs can limit advancements in technology. For instance, federally funded programs don’t always sufficiently target the research and development capabilities of the supply base. (Klier and Sands 2010) An example of this is the U.S. Council for Automotive Research which was established in 1992. This private-public research partnership was established to further research collaboration between the Big Three automakers. The problem with this is that the supply base often has no access to the new research and innovation ideas so they are never able to be implemented. Another issue with this is that this type of partnership doesn’t always drive cutting edge innovations. In most cases, car manufacturers tend to introduce innovation in production vehicles only if they will in turn make a lot of money from the design. In order to maintain the growth of vehicles it is important to spur innovation that will allow the market to stay globally competitive.
While there are drawbacks to federal involvement in the auto industry, the federal government has done a lot to help further the growth phase of this industry. During the 1960s the government created vehicle safety and emission-control laws and the average fuel economy rules in the 1970s. These efforts led to the use of seatbelts, the introduction of the catalytic converter and more fuel efficient engines. (Klier and Sands 2010) These contributions helped improve the safety and performance of vehicles and helped grow the industry.
The Mature Phase
After the growth phase comes a maturity phase, or a period of time when growth levels off and a peak is reached. It is during this phase that the government will typically correct flaws in the market and promote new technologies. The firm can either invest in new ideas or exploit ideas in an attempt to spark growth. The market will then play out in response to changes by the government or firm.
During the mature phase of the automobile industry, attempts were made by the government to try and make the market more competitive. In 2007, Congress passed the Energy Independence and Security Act which was intended to increase fuel efficiency requirements for new vehicles. (Klier and Sands 2010) While this is a step towards making the U.S. automobile industry more competitive with the rest of the world, it does not come close to what Western Europe and Japan are doing in terms of research and development on fuel efficiency.
Often times consumers demand or want to see changes made but are constrained by lock-in conditions in which a customer is dependent on vendors for their products and don’t really have a choice but to settle for what is being offered to them in the current market. An example of this could be with new features on the dashboards of cars. Often times parts on the dashboard are designed to be interchangeable. However, sometimes vendors will sell unusual sized parts or out of the ordinary items which won’t fit with the cars design. This is where the U.S. Department of Transportation steps in to ensure this doesn’t happen and that the consumer isn’t being taken advantage of. In order to get around vendor lock in type situations and spark innovation in mature phases, the government should look to provide more incentives for the consumer. For example in regards to vehicles with better fuel economy, the government could implement a gasoline tax which would encourage the use of more fuel efficient vehicles because people would not be happy paying more at the pump.
In order to further re-invent the automobile industry, the government should also continue to support new research. The government can initiate research by direct grants and by working closely with other federal agencies to ensure they have the support they need for research and development. It is important for the government not to pick winning solutions, and instead fund a variety of competing technologies so that the best alternative or innovation can rise from the pack. (Klier and Sands 2010) Another proposed idea is that the United States Department of Transportation should develop a facility to test new automotive technologies, which are submitted by manufacturers at the prototype stage. This would provide car manufacturers with an early indication of potential new technologies and make information on innovative parts more accessible to car manufacturers in the United States.
Since its birth in the late 1800s, the automobile industry has experienced periods of growth and maturity. Advances in technology have allowed this to remain a primary mode of transportation for commuters in the United States. Early technology has changed significantly to keep up with market development. While there have been motor vehicle fatalities that have happened since the birth of the automobile industry, fatalities have been in a general trend of decline for the last 40 years. Improvements in safety and vehicle design have kept people safe and kept the market interested in the industry. Only time will tell if the steps government and the private sector today are enhancing technology and innovation to keep the automobile a competitive mode in the transportation industry.
AAA. About AAA. http://minneapolis.aaa.com/about-aaa.asp (accessed October 8, 2011).
Bottorff, William W. The First Car - A History of the Automobile. http://www.ausbcomp.com/~bbott/cars/carhist.htm (accessed October 7, 2011).
Brain, Marshall. How Cars Work. http://auto.howstuffworks.com/car.htm (accessed October 6, 2011).
Bridgeman, Roger. 1000 Inventions & Discoveries. New York: DK Publishing, 2002.
Car Safety Features. http://mature.idrivesafely.com/newsletter/Volume1/Issue1/Region8/car-safetyfeatures.html (accessed October 7, 2011).
Cars Auto and Car Information from the People History Site. http://www.thepeoplehistory.com/cars.html (accessed October 9, 2011).
Davis, Kenneth C. Don't Know Much About American History. New York: HarperCollins, 1976.
Economy, Peter. New Car Design. Novato: Treasure Bay, Inc., 2010.
Georgano, Nick. The American Automobile: A Centenary 1893-1993. New York: PRION, 1992.
Klier, Thomas, and Christopher Sands. "The Federal Role in Supporting Auto Sector Innovation." Metropolitan Policy Program, 2010: 1-4.
Motor Vehicle Traffic Fatalities. www.saferoads.org/federal/2004/TrafficFatalities1899-2003.pdf (accessed October 4, 2011).
New York Times. New York's Auto Exports Increase-Big Jump In Cars Shipped Last Year-New Jersey Examines All Drivers. July 14, 1913.
http://query.nytimes.com/mem/archive-free/pdf?_r=1&res=9B07E5DF113CE633A25757C1A9619C946296D6CF (accessed October 8, 2011).
"New York's Auto Exports Increase-Big Jump in Cars Shipped Last Year-New Jersey Examines All Drivers." New York Times. New York: New York Times, July 14, 1913.
Sass, Eric. History of the United States. New York: HarperCollins, 2010.
Speed. http://www.photocop.com/speed.htm (accessed October 8, 2011).
TimeLife. Machines & Inventions. Alexandria: Time Warner, Inc., 1990.