Abstract
We propose a game-theoretic model to study various effects of scale in an insurance market. After reviewing a simple static model of insurer solvency (in which all customers have inelastic demand), we present a one-period game in which both the buyers and sellers of insurance make strategic bids to determine market price and quantity. For the case in which both buyers and sellers are characterized by constant absolute risk aversion, we show that a unique market equilibrium exists under certain conditions. For the special case of risk-neutral insurers, we then consider how both the price and quantity of insurance, as well as other quantities of interest to public-policy decision makers, are affected by the number of insurance firms, the number of customers, and the total amount of capital provided by investors.
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Powers, M.R., Shubik, M. & Yao, S.T. Insurance market games: Scale effects and public policy. Zeitschr. f. Nationalökonomie 67, 109–134 (1998). https://doi.org/10.1007/BF01236065
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DOI: https://doi.org/10.1007/BF01236065