GENERATION OF COHERENT TRIP CHAINS FOR TRAVEL BEHAVIOR ANALYSIS AND MODELING



GENERATION OF COHERENT TRIP CHAINS FOR TRAVEL BEHAVIOR ANALYSIS AND MODELING

Authors

Rita Cyganski, German Aerospace Center, Andreas Justen, German Aerospace Center, Angelika Schulz, German Aerospace Center

Description

The generation of trip chains from National Household Travel Surveys (NHTS), frequently used both directly for data analysis as well as input for transport modeling, usually demands substantial post-processing. Transport models are highly dependent on information on the location type associated with each trip for the proper assignment and consequently estimation of transport flows between origins and destinations. Unfortunately, many NHTS only provide trip purposes without information about specific location types, especially in case of purposes such as ‘pick up / drop off someone’ or ‘accompanying adults’.
Based on the German NHTS ‘MiD 2008 – Mobilitaet in Deutschland’, a step-wise method of data processing is introduced to specify reported locations by investigating the complex household context in which activity and trip planning took place. The step-wise identification of specific location sites considering the household context allows for the generation of additional 11% of qualified trip chains compared to the original data set, thus substantially enhancing the explanatory power of chain-based empirical analysis.
Comparing the effect of different recoding schemes, it can be demonstrated that a systematic consideration of the household context proved most effective for joint trips of adults and children. Detailed recommendations are made to overcome the mainly design-based shortcomings of non-located trip purposes in future NHTS.

Abstract

National Household Travel Surveys (NHTS) serve as data source both in the areas of transport behavior research and transport modeling, where trip chains are often used as analysis unit. Usually, substantial post-processing of data is necessary for the generation of trip chains. Many NHTS only provide trip purposes without information about specific location types, especially in case of purposes such as ‘pick up / drop off someone’ or ‘accompanying adults’. Transport models, however, are highly dependent on such information for estimating transport flows between origins and destinations. Usually, escort trips do not allow for proper assignment of a corresponding location type. Based on the German NHTS ‘MiD 2008 – Mobilitaet in Deutschland’, a step-wise method of data processing is introduced to specify reported locations by investigating the complex household context in which activity and trip planning took place. Locatable trip purposes are transferred between household members using a JAVA-based routine applying several matching criteria of joint trips. Based on selected criteria, coherent trip chains are generated, accounting only for locatable trip purposes. The step-wise identification of specific location sites considering the household context allows for the generation of additional 11% of qualified trip chains compared to the original data set, thus substantially enhancing the explanatory power of chain-based empirical analysis. Comparing the effect of different recoding schemes, it can be demonstrated that a systematic consideration of the household context proved most effective for joint trips of adults and children. Detailed recommendations are made to overcome the mainly design-based shortcomings of non-located trip purposes in future NHTS.

Publisher

Association for European Transport