My dissertation consists of three studies, all viewing aggregate productivity as driven by the individual decisions of firms and the inventors that work for them. I use microeconometric analysis to study why firms innovate and economic theory to link these decisions to macroeconomic outcomes. The first paper in this dissertation studies how German manufacturing firms adjust their productivity in response to an increase in competition from foreign markets. German firms only increase their productivity if their new competitors come from other industrialized economies. This productivity increase is not driven by innovation. Instead, firms cut input expenses and prices while maintaining their output. The second paper traces the matching decisions of firms and inventors on the labor markets of developed economies. It adapts empirical techniques used in labor economics to this special segment of the labor market and shows that assortative matching has been increasing from 1974 to 2012: High quality inventors go to high quality firms more often than was the case in previous decades. This cannot be explained by changes in the patent invention function: The productivity of a match between a firm and an inventor of constant quality remains roughly unchanged. The third paper develops an endogenous growth model with inventor labor markets and two types of innovation: disruptive inventions that change the underlying technology of firms’ products and incremental improvements over existing products. Firms acquire expertise in certain technologies by hiring the inventors who are experts in these fields. This gives them a strong incentive to prevent disruptive inventions: If the underlying technology changes, their investment in these inventors becomes worthless. Large firms inhibit aggregate growth by poaching inventors from firms engaged in disruptive innovation.

This paper studies effects of the introduction of a new digital mass medium on reemployment of unemployed job seekers. We combine data on broadband internet availability at the local level with German individual register data. We address endogeneity by exploiting technological peculiarities that affected the roll-out of broadband internet. Results show that broadband internet improves reemployment rates after the first months in unemployment for males. Complementary analyses with survey data suggest that internet access mainly changes male job seekers’ search behavior by increasing online search and the number of job applications.

This paper studies effects of the introduction of a new digital mass medium on reemployment of unemployed job seekers. We combine data on high-speed (broadband) internet availability at the local level with German individual register data. We address endogeneity by exploiting technological peculiarities that affected the roll-out of high-speed internet. The results show that high-speed internet improves reemployment rates after the first months in unemployment. This is confirmed by complementary analyses with individual survey data suggesting that internet access increases online job search and the number of job interviews after a few months in unemployment.

It is widely unclear as to whether start-up firms supported by publicly-initiated incubator initiatives have higher survival rates than comparable start-up firms that have not received support by such initiatives. This paper contributes to the underlying discussion by performing a large-scale matched-pairs analysis of the long-term survival of 371 incubator firms (after their graduation) from five German incubators and a control group of 371 comparable non-incubated firms. The analysis covers a 10-year time span. To account for the problem of selection bias, a non-parametric matching approach is applied to identify an appropriate control group. For neither of the five incubator locations, we find statistically significant higher survival probabilities for firms located in incubators compared to firms located outside those incubator organizations. For three incubator locations the analysis reveals statistically significant lower chances of survival for those start-ups receiving support by an incubator. The empirical results, therefore, raise some doubts regarding the impacts of incubation on long-term firm survival.

It is widely unclear as to whether start-up firms supported by publicly-initiated incubator initiatives have higher survival rates than comparable start-up firms that have not received support by such initiatives. This paper contributes to the underlying discussion by performing an empirical analysis of the long-term survival of 371 incubator firms (after their graduation) from five German incubators and contrasting these results with the long-term survival of a control group of 371 comparable non-incubated firms. The analysis covers a 10-year time span. To account for the problem of selection bias, a non-parametric matching approach is applied to identify an appropriate control group. For neither of the five incubator locations we find statistically significant higher survival probabilities for firms located in incubators compared to firms located outside those incubator organizations. For three incubator locations the analysis even reveals statistically significant lower chances of survival for those start-ups having received support by an incubator. We therefore arrive at the conclusion that being located in an incubator – contrasting the widespread rhetoric of policy actors and incubator stakeholders – does not increase the chances of long-term business survival.