White S L, Chirikos T N
Preferred Health Care, Ltd., Wilton, Connecticut 06897.
Med Care. 1988 Mar;26(3):256-62. doi: 10.1097/00005650-198803000-00003.
This paper appraises the use of the Herfindahl market share index as an exogenous competition variable in empirical studies of the hospital sector. An analysis of cross-sectional Florida data shows that this index itself is significantly influenced by the demand and supply factors commonly included in econometric models of hospital performance. The analysis then illustrates that biased inferences about the effects of market competition on the costs of hospital care may result unless the values of the Herfindahl Index are treated endogenously in hospital cost models.
本文评估了赫芬达尔市场份额指数在医院部门实证研究中作为外生竞争变量的使用情况。对佛罗里达州横截面数据的分析表明，该指数本身受到医院绩效计量经济模型中通常包含的需求和供给因素的显著影响。然后分析表明，除非在医院成本模型中对赫芬达尔指数的值进行内生处理，否则可能会导致关于市场竞争对医院护理成本影响的有偏差推断。
