Can it be true that most drivers are safer than the average driver?

Area of Science:

• Traffic safety
• Statistical analysis
• Driver behavior

Background:

• Driver self-assessment surveys often show a majority perceive themselves as safer than average.
• This perception has been criticized as statistically impossible, assuming a normal distribution of driver safety.
• Previous analyses overlooked the non-normal distribution of driver accident involvement.

Purpose of the Study:

• To challenge the criticism of driver self-assessment surveys.
• To demonstrate the mathematical possibility of a majority of drivers being safer than average.
• To analyze the distribution of driver accident involvement.

Main Methods:

• Analysis of driver accident data with non-normal distributions.
• Mathematical modeling of accident frequency.
• Estimation of long-term accident expectations based on mean and variance.

Main Results:

• Driver accident involvement follows a skewed distribution, not a normal one.
• Data sets show 70-90% of drivers are safer than the average driver.
• Estimates confirm that the vast majority of drivers are safer than average.

Conclusions:

• The criticism of driver self-assessment surveys is misplaced.
• A skewed distribution of accidents allows for a majority of drivers to be above average in safety.
• Statistical analysis supports the validity of high self-reported driver safety levels.