Abstract
This article analyses two independent data sets to test whether differences in driver behaviour exist between cars equipped with air bags and those not so equipped. An analysis of an insurance industry generated data set reveals that relative injury claims increase following adoption of an air bag system. Since there is no indication that the increase diminishes over time, the results appear to be attributable to off-setting behaviour as opposed to a sorting of auto buyers. Analyses of 1993 Virginia State Police accident reports indicate that air-bag-equipped cars tend to be driven more aggressively and that aggressiveness appears to offset the effect of the air bag for the driver and increases the risk of death to others. (A)