Web-based versus Paper-based Survey Data: An Estimation of Road Users’ Value of Travel Time Savings

Abstract

This study estimates the value of travel time savings (VTTS) by using four types of data sources: stated preference (SP) responses and revealed preference (RP) responses, each from a paper-based survey and a web-based survey. All data were collected in Atsugi City, Japan, in December 2010. In addition to a simple model with SP response data, a combined RP/SP model, a combined paper/web model, and combined RP/SP+paper/web models are formulated to integrate the different data sources. The results show that the VTTS estimated from paper-based survey data could be significantly different to those estimated from web-based survey data. In addition, the combined RP/SP model could improve the model fitness significantly. The combined paper/web model could not improve significantly the model fitness when compared to a paper-only model or web-only model. The combined RP/SP+paper/web model, however, could give the best estimation results, enabling us to obtain reasonable VTTS estimates.