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- 1. Reference: "Dear Mona, Which State Has The Worst Drivers?" , Web. 2 Oct 2015. Dai Chen Carnegie Mellon University Masters of Statistical Practice Which State Has The Worst Drivers? 20 25 30 35 40 20 30 40 50 80 85 90 95 100 25 50 75 100 30000 40000 50000 60000 1980 1990 2000 2010 1. Overview For the entire country, In 2013, there were 32,719 people died in car accidents. These deaths occurred in 30,057 crashes involving 44,868 motor vehicles. This was a decrease in deaths, fatal crashes and motor vehicles involved in fatal crashes over the past four decades, from 1975 to 2013. We are interested in the pattern of these fatal crashes across 51 states in United States. National Average statistics does not include Hawaii and Alaska. Which states have more fatal accidents? A state with more fatal car crashes might be a state that has more drivers or a state with worse driving conditions, so we take the number of accidents divided by the total miles traveled in each state and study the characteristics of the drivers involved in fatal collisions. Two neighboring states on the north, North Dakota and Montana had most such accidents. Arkansas, Kentucky, West Virginia and South Carolina also had a significantly higher fatal accidents compared to other states. The west coast and the north east states had fewer fatal accidents per billion miles. 10 15 20 alabama arizona arkansas california colorado connecticut delaware district of columbia florida georgia idaho illinois indiana iowa kansas kentucky louisiana maine maryland massachusetts michigan minnesota mississippi missouri montana nebraska nevada new jersey new mexico new york north carolina north dakota ohio oklahoma oregon pennsylvania rhode island south carolina south dakota tennessee texas utah vermont virginia washington west virginia wisconsin wyoming new hampshire Idaho Iowa Maine South Dakota Wisconsin North Dakota Ohio North Carolina Indiana Vermont Nebraska New Hampshire Tennessee Virginia Minnesota Kansas Alabama Missouri Wyoming Illinois Oregon Utah Montana Arkansas Colorado South Carolina Hawaii New Mexico Kentucky California Oklahoma Washington Mississippi Arizona Pennsylvania Georgia West Virginia Texas Massachusetts Nevada Maryland Alaska Connecticut Michigan Delaware Rhode Island Florida New York District of Columbia Louisiana New Jersey Idaho Montana Maine South Dakota Oregon Wisconsin Indiana Utah Vermont North Dakota Arizona Washington Iowa Nebraska South Carolina New Hampshire New Mexico Hawaii Wyoming North Carolina Minnesota Ohio Kansas Alaska Massachusetts District of Columbia Kentucky Nevada Illinois Colorado Arkansas Georgia Florida Missouri Alabama Rhode Island New York Delaware Michigan West Virginia Virginia Pennsylvania Tennessee Mississippi Texas New Jersey California Connecticut Oklahoma Maryland Louisiana 200 150 100 50 0 0 500 1000 5 10 15 20 40000 50000 60000 70000 5. Higher Incomes Seem to Associate With Better Drivers 4. Insurance Premium % Speeding % Not Distracted 2. Fatal Collisions Per Billion Miles 3. Characteristics of the Drivers Involved in Fatal Accidents National Average 31 percent. Low states Mississippi. High States In Pennsylvania, 50 percent of the drivers involving in fatal car accidents were speeding. Other High States Texas, Utah, Wyoming, Connecticut, Washington National Average 31 percent. Low States Utah with less than 20 percent. High States Montana, North Dakota, South Carolina (our highest number of fatal accidents rate states from the plot above) Other High States Texas National Average 88 percent. Almost all the states were above 80 percent for drivers who involved in fatal accident did not have crashes before. High States Idaho, Nevada, Maryland, Alabama Low states Kentucky, New Jersey National Average 90 percent. There was a wide range of drivers across the states, as the low states had only 25 percent of drivers that were not distracted, while a lot of states had almost all accidents whose drivers were not distracted. Low states Mississippi, Wisconsin High States Ohio, North Dakota (both 99 percent) We noticed that the west coast and north east states had fewer accidents, and except for South Carolina, these states’ drivers did not involve much in speeding or driving under influence. The graph plots the fatal accidents per billion miles against the median income ($) for each states. It shows a negative correlation between income level and fatal accidents rate. The reason for this phenomena could be that wealthier states have better driving conditions, and drivers in these states are more careful drivers. The average premiums in each state could reflect insurance companies’ overall assessment of who is likely to cost them in the future. The blue bar plot sorts the premium rate from highest to lowest for each state. The national average combined premium was $912 in 2011. The highest average premium rate among the U.S. states was New Jersey ($1,302). The lowest average premium rate was in Idaho, indicating that they could be the best drivers. Another way to see how good the drivers are in each state is to compare the losses that were incurred by insurance. For all collisions, including both fatal and non- fatal, the insurance company paid the least for Idaho drivers. Notice that Louisiana ranked No.2 and No.1 on premium rate and insurance incurred. Motor Vehicles Deaths Crashes Data Source: U.S. Census Bureau, Current Population Survey, 2011 -2013 Annual Social and Economic Supplements. Data Source: National Association of Insurance Commissioners (NAIC), 2010 Data Source: National Highway Traffic Safety Administration (NHTSA), 2009 - 2013 Data Source: National Highway Traffic Safety Administration (NHTSA), 2012 - 2013 Data Source: Insurance Institute for Highway Safety, 2013 Insurance Loss Incurred Per Driver ($) Average Insurance Premium ($) Median Household Income ($) FatalRate % Driving Under Influence % First Accident