中国城镇正规就业与非正规就业的工资差异演变研究——基于非条件分位数回归的分解方法
The Evolution of the Wage Differentials Between Formal and Informal Employment in China：Based on the Method of Unconditional Quantile Regression

基于CHNS历次调查的数据资料，利用非条件分位数回归与分解方法，实证研究1989—2011年三个时期中国城镇正规就业与非正规就业的工资差异问题。研究表明：（1）两个就业群体间的工资差距在不断扩大，正规就业的个体禀赋优势在工资决定中发挥了关键作用；（2）正规就业与非正规就业的工资差距存在不对称性现象，且在工资分布的末端表现明显，符合“黏地板效应”，而造成这一现象的主要原因在于低收入群体存在较为严重的市场分割和就业歧视；（3）由个体禀赋所解释的特征差异呈现上升趋势，而由非市场因素解释的参数差异则在不断下降，反映出我国劳动力市场在整体上趋于公平和完善，工资的决定机制更加以市场为导向。
Based on the CHNS data, and using the method of unconditioned quantile regression, this paper empirically studies the wage differentials between formal and informal employment in 1989—2011. The research shows that：firstly, the wage gap between the formal and informal employment is widening gradually, and the individual endowment advantage plays a proper role in the labor market. Secondly, the wage gap presents a asymmetry phenomenon, which accords with the “sticky floor effect”, and the main reason for the “sticky floor effect” is the labor market’s segmentation and employment discrimination in the low income groups. Thirdly, the characteristics difference is increasing and the parameter difference is declining, which explains the reason for the growing income gap between formal and informal employment, and reflects the labor market tending to be more fair and perfect, and the market mechanism is stronger.