抄録
This paper proposes a method for sequential updating of the short-run and long-run price elasticities of traffic demand incorporating regional differences based on hierarchical Bayesian approach. The elasticities are treated as uncertain elements and updated to make an adjustment of our expectations/beliefs in the behavioral responses. As an empirical analysis, the updating is demonstrated from January through August in 2008 by using monthly traffic volume data on 54 expressway routes in Japan, which include two notable periods: the outdated temporary tariff rate (during April 2008) and the rapid increase of gasoline price (until August 2008). The results show that, even within a year, the short-run and long-run elasticities are quite unstable across space and over time, and underscore that we should make a continued observation of both short-run and long-run elasticities in order to monitor the change of behavioral responses to gasoline price fluctuations.
