Insurance, in law and economics

Insurance, in law and economics, is a form of risk management primarily used to hedge against the risk of a contingent loss. Insurance is defined as the equitable transfer of the risk of a loss, from one entity to another, in exchange for a premium. Insurer is the company that sells the insurance. Insurance rate is a factor used to determine the amount, called the premium, to be charged for a certain amount of insurance coverage. Risk management, the practice of appraising and controlling risk, has evolved as a discrete field of study and practice.

Commercially insurable risks typically share seven common characteristics.[1]

A large number of homogeneous exposure units. The vast majority of insurance policies are provided for individual members of very large classes. Automobile insurance, for example, covered about 175 million automobiles in the United States in 2004.[2] The existence of a large number of homogeneous exposure units allows insurers to benefit from the so-called “law of large numbers,” which in effect states that as the number of exposure units increases, the actual results are increasingly likely to become close to expected results. There are exceptions to this criterion. Lloyd's of London is famous for insuring the life or health of actors, actresses and sports figures. Satellite Launch insurance covers events that are infrequent. Large commercial property policies may insure exceptional properties for which there are no ‘homogeneous’ exposure units. Despite failing on this criterion, many exposures like these are generally considered to be insurable.