Value Of Service Reliability Research Articles

The value of service reliability

This paper studies the impact of service frequency and reliability on the choice of departure time and the travel cost of transit users. When the user has (α,β,γ) scheduling preferences, we show that the optimal head start decreases with service reliability, as expected. It does not necessarily decrease with service frequency, however. We derive the value of service headway (VoSH) and the value of service reliability (VoSR), which measure the marginal effect on the expected travel cost of a change in the mean and in the standard deviation of headways, respectively. The VoSH and the VoSR complete the value of time and the value of reliability for the economic appraisal of public transit projects by capturing the specific link between headways, waiting times, and congestion. An empirical illustration is provided, which considers two mass transit lines located in the Paris area.

Value of service reliability

The authors present the value of service (VOS) reliability evaluation approach, which explicitly incorporates into the planning process customer choices regarding reliability 'worth' and service costs. Using the least-cost planning framework and taking advantage of the recent advances in the quantification of outage costs, this approach determines the optimal level of reliability for the utility and its customers. The approach considers system operational measures-the so-called emergency actions-that the operators invoke in times of dwindling reserves. Information on customer outage costs associated with such actions is incorporated using a probabilistic framework. This approach permits utilities to plan for levels of reliability commensurate with the customers' willingness to pay. The application of this methodology to planning problems is discussed. Numerical results for a large utility are presented. >