Assessing the accuracy of driver passenger counts : the experience of ac transit.

Passenger counts by bus drivers are subject to unknown errors. A sample of regular counts by AC transit drivers, using electronic registering fareboxes, was compared to accurate counts taken by on-board checkers. Some of the counts read from the fareboxes are wildly inaccurate, probably for reasons other than driver error. If these are eliminated, the remaining counts average 94 percent of the true count. Patterns of error were found that suggest the possibility of developing correction formulas. Low driver counts correlate with high monthly pass usage, low use of cash fares in general, and high measured average cash fares.