关键词: 流动人口, 非正规就业, 工资差异, 倾向值分析

Abstract: Using multiple propensity score methods，including propensity score geedy matching，propensity score optimal matching，propensity score weighting and matching estimator，this paper analyzes wage differentials between formal and informal employment of migrant workers． The results show that the two groups of migrant workers differ significantlly in education，work experience and other personal chracteristics．Resulting from these selection biases，the t test and the OLS regression would overestimate the average treatment effect of formal employment on wage． After controlling the selection biases，there are statistically significant wage differentials between the two groups，which confirms the market segmentation between formal and informal employment and the discrimination against informal employmee in the labor market of floating population．

Keywords: Floating Population, Informal Employment, Wage Differentials, Propensity Score Analysis