SUPERVISOR: Astrid GÜHNEMANN

PROJECT ASSIGNED TO: Lukas HARTWIG 

Transport is the sector that routinely fails to achieve the greenhouse gas emission reduction targets put in place by national and international legislation to combat climate change and transition to a sustainable transport system (Anderl et al., 2022). This emphasises that next to existing measures like the gradual electrification of the car fleet additional measures are necessary to achieve the climate targets. One measure with a significant emission reduction potential is shifting car trips to more sustainable modes such as walking, cycling and public transport (PT) (Nelldal & Andersson, 2012).

One major barrier for travellers to use public transport, if it is available, is that the travel time is usually longer than with the car. There are measures to speed up PT travel and/or slow down cars in order to bridge this gap, but some difference might remain. However, travel time in PT is different from travel time in a car, because it can be used for a whole range of activities that are not possible while driving. The way travel time is perceived is conventionally measured by the willingness-to-pay to reduce travel time, called the Value of Travel Time Savings (VTTS), where a higher VTTS is associated with higher levels of inconvenience.

Previous research has established that the VTTS of PT passengers is typically lower than the VTTS for car drivers with typical ratios of PT to car of 0.81 – 1.10 (Wardman et al., 2016). This could be due to several reasons: self-selection of individuals with a lower value of time (Schmid et al., 2019), higher comfort in PT (e.g., not having to pay attention to traffic), or the possibility to conduct other activities while travelling which is called travel-based multitasking. The fact that more recent studies report even lower VTTS ratios points to the role of mobile digital devices which have become more and more widespread and enable a whole range of new multitasking activities while travelling (de Jong & Kouwenhoven, 2020).

The effect of multitasking on the VTTS has mostly been evaluated through revealed-preference studies that suffer from hypothetical bias which means that survey respondents do not actually make the trip and perform the multitasking activity that they choose in the survey (Krčál et al., 2019). Revealed preference data does not have this bias, but it is much harder to obtain the attributes of all non-chosen alternatives for the trip that was reported/chosen. These alternatives are needed to estimate VTTS with mode choice models and consequentially there are only very few suitable revealed-preference data sets available.

This is why we decided to create an innovative survey format that combines a mobility- and activity survey and includes questions on travel-based as well as stationary multitasking with an extensive data preparation process in which the attributes for non-chosen alternatives and the potential multitasking activities for these alternatives are inferred. During the data collection, the first lockdown due to the COVID-19 pandemic was imposed in Austria. This has potentially affected the mobility and activity patterns of the survey participants and has to be accounted for.

 

RESEARCH OBJECTIVES:

  • Develop, conduct and evaluate an innovative mobility and activity survey with questions on multitasking in order to obtain a suitable data set
  • Determine the effect that the COVID-19 pandemic and the resulting measures had on the reported trips and activities in the data set
  • Estimate the influence of travel-based multitasking on the VTTS

 

REFERENCES:

Anderl, M., Bartel, A., Frei, E., Gugele, B., Gössl, M., Mayer, S., Heinfellner, H., Heller, C., Heuber, A., Köther, T., Krutzler, T., Kuschel, V., Lampert, C., Miess, M. G., Pazdernik, K., Perl, D., Poupa, S., Prutsch, A., Purzner, M., … Zechmeister, A. (2022). Klimaschutzbericht 2022. www.umweltbundesamt.at.

de Jong, G., & Kouwenhoven, M. (2020). Chapter Two - Value of travel time and travel time reliability. In N. Mouter (Ed.), Standard Transport Appraisal Methods (Vol. 6, pp. 43–74). Academic Press. doi.orghttps://doi.org/10.1016/bs.atpp.2020.07.010

Krčál, O., Peer, S., Staněk, R., & Karlínová, B. (2019). Real consequences matter: Why hypothetical biases in the valuation of time persist even in controlled lab experiments. Economics of Transportation, 20. doi.org/10.1016/j.ecotra.2019.100138

Nelldal, B.-L., & Andersson, E. (2012). Mode Shift as a Measure to Reduce Greenhouse Gas Emissions. Procedia - Social and Behavioral Sciences, 48, 3187–3197. doi.org/10.1016/j.sbspro.2012.06.1285

Schmid, B., Jokubauskaite, S., Aschauer, F., Peer, S., Hössinger, R., Gerike, R., Jara-diaz, S. R., & Axhausen, K. W. (2019). A pooled RP / SP mode , route and destination choice model to investigate mode and user-type effects in the value of travel time savings.

Wardman, M., Chintakayala, V. P. K., & de Jong, G. (2016). Values of travel time in Europe: Review and meta-analysis. Transportation Research Part A: Policy and Practice, 94, 93–111. doi.org/10.1016/j.tra.2016.08.019