# On Decision Principles for Routing Strategies Under Various Types of Risks

## Abstract

Individual travellers as well as freight operators face several sources of risk and uncertainty while choosing their path. This chapter looks at the case when the decision maker is uncertain about how many incidents could disrupt the trip and compares different levels of information regarding the incident likelihood on each link. The first part of the paper looks at the route choice as a game against nature in which route choice and incident probability are independent. The second part of the paper considers cases where incident probability depends on the link use. The solution to a game against an intelligent entity (worst case, no information) is compared with the case when the information about incident likelihood is available. A simple solution algorithm is proposed to find the optimal routing strategy when incident probability is a function of link use probability, and the results are illustrated on a small network. The results show that using multiple routes reduces the potential exposure to loss not only when the worst case scenario is assumed, but also can bring potential benefits when information about incident likelihood is available.

## Keywords

Path selection Risks game theory incident probability information## References

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