Accounting for Selection Effects in the Analysis of Wage Inequality in Germany

该项目的目的是分析过去几十年来德国工资不平等的加剧。为了评估所观察到的工资分布变化的驱动因素以及劳动力市场群体之间的工资差异，重要的是要考虑到有偿工作的选择可能会随着时间的推移而变化，并且可能在群体之间有所不同。鉴于就业波动、长期就业增长、女性劳动力参与率上升以及向非全时工作的转变，构成变化对分析工资不平等非常重要。该项目量化了不同群体之间和不同时间的工资分配差异，这些差异不包括工作服务和未观察到的工人特征的差异。到目前为止，本项目使用DiNardo等人（1996）的重加权方法和Firpo等人（2014）的RIF回归方法，分析了可观察特征的构成和工资结构效应。使用Albrecht et al.（2009）的方法对性别工资差距进行了分析，控制了对不可观测值的选择。关于如何在结果分布分析中控制不可观测值的选择，只有一小部分但最近非常活跃的方法学文献，参见Huber和melanie (2015)， Arellano和Bon-homme(2016)，以及D'Hautefoeuille等人（2017）。第二个资助期的项目建议包括五个部分：第2A部分扩展了第一个项目阶段的工作，并详细探讨了估计工资数据的分位数回归和选择校正所涉及的方法问题。这一部分的目的是在文献最新发展的基础上做出方法学贡献，并作为实证分析的方法学基础。第2B部分估计了分位数回归与选择校正，以详细分析工资随时间的演变。我们通过分析为什么德国工资不平等的增加在2010年结束来扩展之前的工作。本部分将侧重于不同数据集的适用性和不同工具的适用性，以控制选择进入基于不可观察的有偿工作。第二部分分析了性别工资差距，同时考虑到广泛的方法方法，也纠正了不可观察的选择。第2部分论述了教育的大规模扩张如何影响教育学位的质量和回报的问题。我们将研究这样一个假设：高等教育的扩招使毕业生的平均素质下降，从而降低了高等教育的回报。第二部分分析了个体劳动力市场转型变化与工资演进之间的关系。我们将特别关注临时非全日制工作的增加和男性非全日制工作的显著增加所带来的影响。”

The objective of this project is to analyze the rise of wage inequality in Germany over the last decades. For an assessment of the drivers for the observed changes in the wage distribution and the wage dif-ferences between labor market groups, it is important to take into account that the selection into paid work may change over time and may differ across groups. In light of employment fluctuations, long-term employment growth, rising female labor force participation, and a shift towards part-time work, composition changes are very important for the analysis of wage inequality. This project quantifies the differences in wage distributions between groups and over time that are free of differences in ob-served and unobserved worker characteristics. So far, this project has analyzed the composition and wage structure effects of observable characteristics, using the reweighting approach by DiNardo et al. (1996) and the RIF regression approach of Firpo et al. (2014). Selection on unobservables has been controlled for using the method of Albrecht et al. (2009) in the analysis of the gender wage gap. There exists only a small but recently very active methodological literature on how to control for selection on unobservables in the analysis of outcome distributions, see Huber and Melly (2015), Arellano and Bon-homme (2016), and D'Hautefoeuille et al. (2017). The project proposal for the second funding period consists of five parts: Part 2A extends work from the first project phase and explores in detail the methodological issues involved in estimating quantile regression for wage data with selection correction. This part aims to make a methodological contribution building on recent developments in the literature and serves as a methodological basis for the empirical analysis. Part 2B estimates quantile regressions with selection correction for a detailed analysis of the evolution of wages over time. We extend the previous work by also analyzing as to why the increase in wage inequality in Germany has come to an end in 2010. This part will focus on the suitability of different datasets and the suitability of different instruments to control for selection into paid work based upon unobservables. Part 2C analyzes the gender wage gap, while also correcting for selection on unobservables considering a wide range of methodological approaches. Part 2D addresses the question of how the considerable educational expansion has influenced the quality and the returns to educational degrees. We shall study the hypothesis that increasing enrollment in higher education has deteriorated the average quality of graduates and thus reduced the returns to higher education. Part 2E analyzes the relationship between changes in individual labor market transitions and the evolution of wages. In particular, we will focus on the effects of increasing incidence of temporary part time work and the notable increase in male part-time work.