Returns to Scale in the Swedish Property-Liability Insurance Industry
利用瑞典财产责任保险业1977年的横截面数据，研究发现用赔付额衡量规模时存在规模经济，而用保费收入会低估规模经济，对理解保险业成本结构有参考价值。
Cross-section regressions are used to evaluate the extent of economies of scale in the Swedish Property-Liability Insurance (PLI) industry. Due to the presence of insurance regulation in Sweden, unusually good (disaggregated) data are available. The measure of size used in earlier studies premium income results in downward biased estimates of economies of scale. A more adequate measure used here compensations paid. Economies of scale are found for general PLI for 1977. Economies are also detected for auto insurance prior to 1960. The results are consistent with the notion that economies arise largely in the process of claimadjustment. The Swedish Insurance Business Act of 1948, as extended in 1952 to property-liability insurance, states that a potential entrant shall receive a concession to operate in the PLI-industry if the firm is needed and contributes to the sound development of the market. The expressed motivation for this statute was that the insurance industry contained too many small insurers'. Since 1952, the Insurance Industry Supervisory Board, which the major regulatory body for private insurance companies in Sweden, has actively encouraged industry concentration as a means of economizing on administration costs2. However, no rigorous analysis of the cost structure of insurers and of the possible presence of economies of scale has ever been conducted. Goran Skogh a lecturer at the University of Lund, Sweden. He earned Fil. kand. and Fil dr. degrees from the same institution. Dr. Skogh currently conducting research financed by a grant from the Swedish Council for Research in Humanities and Social Sciences. He was an assistant professor at the University of Lund from 1968 to 1978, an acting professor at the University of Uppsala during 1978-79, and a visiting professor at the University of Florida at Gainesville. His major fields are Law and Economics. He has published several reports and articles in United States and Swedish professional journals. The author grateful to the Swedish Council for Research in Humanities and Social Sciences for financial support. Thanks are due to co-workers Carl Martin Roos and Charles Stuart, and to Ingemar Hansson, Bernard Lentz, Erling Pettersson, and an unknown referee for helpful comments. 1[9], p. 150 f. 2This p6licy has had several effects. For instance, no new concessions have been granted for the selling of homeowner's or tenants' insurance since 1952. In 1951, there were 58 firms selling such insurance, and the three largest domestic firms had a market share of 20 percent of total sales. By 1977, there were 20 firms in business in this market and the market share of the three largest firms had grown to 70 percent. In addition, sale-share of foreign firms fell from 8 percent to 2 percent during the period.