Supported by the National Natural Science Foundation of China(No.11301475,11126202,11171207);the Nature Science Foundation of Zhejiang Province(No.LQ12A01011);partially supported by The Hong Kong CERG Research Fund PolyU 5515/10H
The backup 2-median problem is a location problem to locate two facilities at vertices with the minimum expected cost where each facility may fail with a given probability. Once a facility fails, the other one takes f...