Airlines as baseball players: another approach for evaluating an equal-safety hypothesis

Within the First World, observed differences across air carriers in passenger death risk are almost never statistically significant. But given the rarity of fatal crashes, even a lopsided split of crashes across airlines is unlikely to achieve significance. For greater perspective about relative airline safety performance, we supplemented an analysis of overall mortality data with a two-part statistical procedure. The first part – which was inspired by the way the Oakland Athletics Major League baseball team evaluates individual baseball players – allows for a sharp test of a key aspect of an equal-safety hypothesis, related to the frequency with which individual airlines suffer life-threatening events. The second test considers a further aspect of safety, namely the ability to recover from emergencies given that they have occurred. When applied to U.S. domestic jet services over 1983–2002, the test procedures indicate that long-established airlines have been about equally (and hugely) successful in protecting their passengers from accidental death and that established airlines are not demonstrably safer than the ‘new-entrant’ jet carriers formed after U.S. airline deregulation.