An operator of public transport services attempts to reduce the door-to-door travel times in order to compete better with the private car. However, only a limited part of public transport travel time can be influenced directly. Planning margins in the running time of the train and the transfer time must be as little as possible to minimize the published travel time. These planning margins compensate, however, the perturbations in the operation of a train service. When planning margins are reduced, punctuality and reliability will diminish. This finally results in a decrease in the number of train travellers, as shown in a case. The reason is that more passengers will miss the connecting train and the extra travel time weighs relatively heavily. (A)
Abstract