Waiting tolerance: Ramp delay vs. freeway congestion

Waiting at ramp meters and traveling on freeways were tested using a computer administered stated preference (CASP) survey and a virtual experience stated preference (VESP) method employing a driving simulator. The selections varied in the number of minutes waiting at a ramp meter with vehicle speed once on the freeway. The subjects ranked the selections in order of preference. The results were statistically analyzed using a binary logit model controlling for demographics, socioeconomic characteristics, daily travel time, and personality scores. The results by the CASP method displayed a preference for freeway congestion to ramp delay, but opposite results were obtained by the VESP method. A number of reasons are posited to explain the difference, but the results indicate that method of stated preference data collection can significantly affect conclusions drawn.