6.On the Issue of “The last mile”
The perceived cost of transfer time is typically found to be much higher than in-link (line haul) time.
In some cases (e.g. PBQD Inc. 1993), the penalty of transfer is found to be so significant that it can be weighted up to the scale of hundreds of in-vehicle traveling time, which makes the transfer critical in the overall level of service.
However, the traditional metrics of measure of performance, which usually emphasize on travel cost, are by all means oversimplified.
Besides the readily quantifiable measure of performance, the negative utility of transfer is resultant from other elements that contributes to the perception of the existing measure of performance.
For example, when people are transferring from a rail station to an airport, their preference of people mover or moving walk to walking is obvious.