The goal of this paper has been to assess the factors that influence the sensitivity of travelers to public transport travel costs in Europe, by carrying out a comparative analysis of elasticity values of trans- port demand resulting from studies in various coun- tries. We have made use of a rather limited data set containing 12 studies/surveys on demand elasticities with 8 site- and study-specific characteristics. Be- cause of this, we had only a few degrees of freedom. By applying meta-analysis, this comparative study has still led to some interesting conclusions.
The main findings from existing reviews of elas- ticity studies assessing causes of variances— name- ly the importance of the difference between aggregated, empirical-based research methods and disaggregated choice models, as well as the model assumptions—seem to be reasonably supported by our indepth analysis of a set of potential factors of influence by means of rough set analysis. It appears that from our set of variables, country, number of competitive modes, and type of data collected have the strongest explanatory power for the elasticity size. The result of our meta-analytic application is that in addition to the practical findings on the dif- ference between empirical-based research methods and the use of disaggregated choice models, coun- try-specific factors also play a large role. This means that care should be taken when comparing elasticities for the different European countries, even when estimation methods are the same (i.e., data used and the model specification). Relevant country-specific characteristics like natural circum- stances and travel distances may mean that certain modes are favored (e.g., the bicycle in the Netherlands). Cultural differences and differences