Traditionally, insurance risks are borne in reinsurance markets. In 1990s, however, after the sequence of huge natural disasters and huge insurance payments, the reinsurance markets reduced its capability to bear risks, especially those related to catastrophic natural disasters....

This paper proposes risk sharing strategies, which allow insurers to cooperate and diversify non-systemic risk. We deal with both deviation measures and coherent risk measures and provide general mathematical methods applying to optimize them all. Numerical examples are given in order to...