Coping with unreliability in public transport chains

Unreliability in public transport means that actual departure and arrival times may deviate from the official timetable. Data on unreliability are usually uni-modal. In this paper we address unreliability from a multimodal perspective, implying a shift of attention away from the supplier towards the customer. Estimates of unreliability of public transport chains in the Netherlands are provided. In addition, customer valuation of unreliability is estimated. We find that the valuation of a certain travel time loss of 1 minute is 27 cents, whereas the valuation of a 50% probability of a 2 minute delay is 64 cents. This implies a strong attitude of risk aversion towards travel time of passengers. On the basis of these values an evaluation of probability enhancing strategies has been carried out. We conclude that among the most promising means of improving the overall quality of the chains is that travellers use the bicycle as an entrance or exit mode. Other measures which are relatively inexpensive to implement and result in fairly large gains for the average public transport passenger, are an increase in transfer times and a strict constraint on bus drivers to prevent them from departing early.