Robust models for transportation service network design

- Two new robust models for transportation service network design.
- Base assumption is knowledge of mean and upper bound on demand.
- Base assumption supplemented by variance and lower bound information.
- Relationship between models analytically characterized.

In this paper robust models are presented for the transportation service network design problem, using the ferry service network design problem as an example application. The base assumption is that only the mean and an upper bound on the passenger demand are known. In one robust model, this information is supplemented by a lower bound on the demand, whereas in a second robust model, the assumption is made that the variance of the demand is known, in addition to the mean and upper bound. The relationship between the two models is investigated and characterized analytically. A case study using the ferry service in Hong Kong is provided to illustrate the models.