Impact of Censoring on Estimation of Flow Duration Distribution and Its Mitigation Using Kaplan-Meier-Based Method

A basic and inevitable problem in estimating flow duration distribution arises from “censoring” (i.e., cutting off) the observed flow duration because of a finite measurement period. We extended the KaplanMeier method, which is used in the survival analysis field, and applied it to recover information on the flow duration distribution that was lost due to censoring. We show that the flow duration distribution from a short period of actual traffic data with censoring that was estimated using a KaplanMeier-based method can approximate well the flow duration distribution calculated from a sufficiently long period of actual traffic data. key words: flow duration distribution, censoring, Kaplan-Meier method