Katrin Sommerfeld

Rising Wage Inequality, the Decline of Collective Bargaining, and the Gender Wage Gap

This paper investigates the increase in wage inequality, the decline in collective bargaining, and the development of the gender wage gap in West Germany between 2001 and 2006. Based on detailed linked employer-employee data, we show that wage inequality is rising strongly – driven not only by real wage increases at the top of the wage distribution, but also by real wage losses below the median. Coverage by collective wage bargaining plummets by 16.5 (19.1) percentage points for male (female) employees. Despite these changes, the gender wage gap remains almost constant, with some small gains for women at the bottom and at the top of the wage distribution. A sequential decomposition analysis using quantile regression shows that all workplace related effects (firm effects and bargaining effects) and coefficients for personal characteristics contribute strongly to the rise in wage inequality. Among these, the firm coefficients effect dominates, which is almost exclusively driven by wage differences within and between different industries. Labor demand or firm wage policy related effects contribute to an increase in the gender wage gap. Personal characteristics tend to reduce wage inequality for both, males and females, as well as the gender wage gap.

Causal effects on employment after first birth — A dynamic treatment approach

The effects of childbirth on future labor market outcomes are a key issue for policy discussion. This paper implements a dynamic treatment approach to estimate the effect of having the first child now versus later on future employment for the case of Germany, a country with a long maternity leave coverage. Effect heterogeneity is assessed by estimating ex post outcome regressions. Based on SOEP data, we provide estimates at a monthly frequency. The results show that there are very strong negative employment effects which are causally due to childbirth. Although the employment loss is reduced over the first five years following childbirth, it does not level off to zero. We find a significant reduction in the employment loss over time.

Older Babies - More Active Mothers? How Maternal Labor Supply Changes as the Child Grows

Female labor market activity is dependent on the presence and the age of a child, but how do the determinants develop in magnitude and significance with the childs age? Using German SOEP data from 1991 to 2006 for mothers with young children, the change in maternal labor supply when the child is one, two, and three years old is explicitly addressed. According to the tobit regression results for precise working hours, maternal labor supply becomes increasingly responsive to economic incentives - mainly to imputed wages - as the child grows.

Higher and Higher? Performance Pay and Wage Inequality in Germany

Performance pay is of growing importance to the wage structure as it applies to a rising share of employees. At the same time, wage dispersion is growing continuously. This leads to the question of how is the growing use of performance pay schemes related to the increase in wage inequality? German Socio-Economic Panel (SOEP) data for the years 1984 -- 2009 confirm the large increase in the application of performance pay schemes. This in turn led to an upward shift of the wage distribution by about one log point. However, it did not contribute to the growth in wage inequality. Even though wage inequality grew within the group of employees who receive performance pay, it grew even more so within the group who do not. Still, the wage difference between both wage schemes remained flat over the distribution. The empirical analysis employs sequential decompositions in a quantile regression framework.

Causal effects on employment after first birth - A dynamic treatment approach -

The effects of childbirth on future labor market outcomes are a key issue for policy discussion. This paper implements a dynamic treatment approach to estimate the effect of having the first child now versus later on future employment for the case of Germany, a country with a long maternity leave coverage. Effect heterogeneity is assessed by estimating ex post outcome regressions. Based on SOEP data, we provide estimates at a monthly frequency. The results show that there are very strong negative employment effects after childbirth. Although the employment loss is reduced over the first five years following childbirth, it does not level off to zero. The employment loss is lower for mothers with a university degree. It is especially high for medium-skilled mothers with long prebirth employment experience. We find a significant reduction in the employment loss for more recent childbirths.

Why does emissions trading under the EU Emissions Trading System (ETS) not affect firms’ competitiveness? Empirical findings from the literature

ABSTRACT Environmental policies may have important consequences for firms’ competitiveness or profitability. For the European Union Emissions Trading System (EU ETS) the empirical literature documents that significant emissions reductions have resulted from it. Surprisingly, however, the literature shows that there have been hardly any concurrent negative effects on firms’ competitiveness during the first two phases of the scheme (2005–2012). We show that the main explanations for the absence of negative impacts on competitiveness are a large over-allocation of emissions allowances leading to a price drop and the ability of firms to pass costs onto consumers in some sectors. Cost pass-through combined with free allocation, in turn, partly generated windfall profits. In addition, the relatively low importance of energy costs indicated by their average share in the budgets of most manufacturing industries may have limited the impact of the EU ETS. Finally, small but significant stimulating effects on innovation have been found so far. Several factors suggest that over-allocation is likely to remain substantial in the upcoming periods of the scheme. Therefore, we expect to see no negative competitiveness effects from the EU ETS in Phases III and IV (2013–2030). Key policy insights Empirical literature on the EU ETS shows that there have been hardly any effects on firms’ competitiveness or profitability. One main explanation is a large over-allocation of emissions allowances leading to a price drop. This reduced incentives for innovation. Moreover, firms were able to pass costs on to consumers in some sectors which partly generated windfall profits. Innovation effects have so far been small but positive. We expect to see no negative competitiveness effects on regulated firms in the near future suggesting that no further reliefs for regulated firms are required.

Drivers of energy efficiency in German manufacturing: A firm-level stochastic frontier analysis

Increasing energy efficiency is one of the main goals in current German energy and climate policies. We study the determinants of energy efficiency in the German manufacturing sector based on official firm-level production census data. By means of a stochastic frontier analysis, we estimate the cost-minimizing energy demand function at the two-digit industry level using firm-level heterogeneity. Apart from the identification of the determinants of the energy demand function, we also analyze potential drivers of energy efficiency. Our results suggest that there is still potential to increase energy efficiency in most industries of the German manufacturing sector. Furthermore, we find that in most industries exporting and innovating firms as well as those investing in environmental protection measures are more energy efficient than their counterparts. In contrast, firms which are regulated by the European Union Emissions Trading System are mostly less energy efficient than non-regulated firms.

A Sequential Decomposition of the Drop in Collective Bargaining Coverage

Union representation has been in strong decline in most OECD countries with potentially important consequences for wages. What drives this decline? We try to answer this question by developing and implementing a detailed decomposition approach based on Fairlie (2005). Using linked employer-employee data from the German Structure of Earnings Survey for 2001 and 2006, we document a sharp drop in collective bargaining coverage that amounts to 17 percentage points for males and 20 percentage points for females in West, and eight and 14 percentage points, respectively, in East Germany. We find that neither changes in the characteristics nor changes in the coefficients associated with the characteristics as a whole provide an explanation for the drop in collective bargaining coverage. The drop in coverage is the result of an unexplained time trend.