Travel mode switching: Comparison of findings from two public transportation experiments

In previous research, we conducted a small-scale experiment in Switzerland to study the effect of a temporary use of public transportation by habitual car drivers on their commute satisfaction and mode switching. This paper reports findings from a similar experiment conducted at the Massachusetts Institute of Technology (MIT) with a larger sample, focusing on mode switching differences between the two experiments. Whereas none of the Swiss participants switched, about 30% of MIT participants switched to public transportation after the intervention (or treatment). An analysis of the underlying reasons for these differences is presented, including individual socio-demographic factors, travel attributes and institutional transportation policies, experiment context, social influences, and psychological variables. The individual and behavioral variables are compared between those who switched to public transportation and those who did not, and pre- to post-treatment changes are analyzed. Those who switched to public transportation were more predisposed to switching, were more cost-conscious, and had more favorable perceptions and attitudes towards public transportation. Those who did not switch became happier with their cars. Implications for mode switching policies employing free public transportation tickets and for institutional transportation policies are drawn.