Workshop Synthesis: Representativeness in surveys: challenges and solutions

During this workshop on “representativeness in surveys: challenges and solutions” for mobility surveys, we discussed various issues of representativeness in travel surveys. Issues such as lack of coverage of sampling frames, nonresponse mechanism and measurement error bias were investigated along with models that can help to reduce the impacts of these issues and preserve data quality for transport analysis. According to the participants of the workshop, the best way to avoid problems with representativeness in surveys is to tackle the problem upstream (good sampling frame, follow-up with respondents, incentives, response facilitators, etc.). But still at the end of the day we will need to reweigh the respondent sample to account for differential probabilities of selection among subgroups; effects arising from nonresponse; inadequacies in sample frame, etc. and bring the respondent sample data up to the dimension of the study population.