1Haddad, L. and Bouis, H. E. , The Impact of Nutritional Status on Agricultural Productivity: Wage Evidence from the Philippines, Oxford Bulletin of Economics and Statistics, 1991, 53 ( 1 ) :45 -68.
2Heckman J. J. , Sample Selection Bias as a Specification Error, Econometrica, 1979, 47 ( 1 ) :153 - 161.
3Holzmann R. and Jorgensen S. , Social Risk Management: A New Conceptual Framework for Social Protection and Beyond, Social Protection Discussion Paper No. 0006, 2000 : 1 - 30.
4Gravelle,Wildman and Sutton. Income, income inequality and health:what can we learn from aggregate data? [ J ]. Social Science & Medicine,2002,54(4) : 577 - 589.
5Li and Zhu. Income, income inequality, and health : Evidence from China [ J ]. Journal of Comparative Economics, 2006,34 ( 4 ) : 668 - 693.
6卫生部信息统计中心.第四次国家卫生服务调查分析报告.http://WWW.moh.gov.cn.
7Heckman J. Sample selection bias as a speci{ication error[J]. Economitrica, 1979,47(1) .. 153-161.