In the course of the study, speed and other characteristics such as age, sex military status and residence of the driver; types of vehicles and the horsepower, body style and age of passenger cars were related to accidents. Involvement rate was the key to the analysis problem. Accident reports, for example, frequently show the estimated travel speeds of vehicles involved in highway accidents. It is not enough, however, to know that a certain number of drivers involved in accidents were travelling at a particular speed; it is also essential to determine how much driving was done at that same speed. Then, by relating the travel speeds of accident involved drivers and of all drivers it is possible to determine the hazard associated with specific driving speeds- the accident-involvement rate. Simply put, an accident involvement rate represents the number of involvements per 100 million miles of travel. A description of the procedure used in obtaining the data and the resultant findings relating speed driver, and vehicle characteristics to reported accidents on main rural highways in the United States are included in this publication. Apart from the accident analysis, some subsidiary analyses, some subsidiary analyses of travel patterns and speed also have been included.
Abstract