성별 차이가 근로소득 과세표준에 미치는 분위 효과 분석

Abstract

This paper analyzes the quantile effect of gender differences on the labor income tax base by estimating the counterfactual distribution proposed by Chernozhukov et al.(2013). The counterfactual distribution is the hypothetical distribution which is obtained when male taxpayers are subject to the conditional distribution of the tax base of female taxpayers given the same covariate vector. The quantile effect is decomposed into two types of quantile effects. The first type of the quantile effect is due to the difference between the distribution of male taxpayer’s tax base and the male taxpayer’s counterfactual distribution. It reflects the structural difference of tax base determination, which is due to the gender difference in spite of the same characteristics. The second type of the quantile effect is due to the difference in the distribution of the covariate vector by gender when the conditional distribution of the tax base given covariate vector is the same to both male and female taxpayers. The estimation results show that the quantile effect is mainly due to the second type of quantile effect. The second type of quantile effect was found to have statistically significant positive effects at every quantile, which implies that the male taxpayer’s tax base is larger than the female taxpayer’s because of the discrepency between male and female distributions of covariate vector. On the other hand, the estimation results show that the first type of the quantile effect was non-positive except for a few quantiles. This suggests that the male taxpayer’s tax base is mostly smaller than that of the female taxpayer’s when male and female taxpayers have the same covariate vector. The first type of the quantile effect is found to have statistically negative significance only at low and middle quantiles, specifically less than 10th percentile and between 40th and 50th percentiles. It means that the male taxpayer’s tax base would increase if the male taxpayer at the low and middle quantiles is subject to the female taxpayer’s conditional distribution of the tax base given the same covariates.