Wage rigidity is an important explanation for unemployment fluctuations. In benchmark models wages for new hires are key, but there is limited evidence on this margin. We use wages posted on vacancies, with job and establishment information, to measure the wage for new hires. We show that our measure of the wage for new hires is rigid downward and flexible upward, in two steps. First, wages change infrequently at the job level, and fall especially rarely. Second, wages do not respond to rises in unemployment, but respond strongly to falls in unemployment. Job information is crucial for detecting downward rigidity.

We examine the role of technological change in explaining the large and persistent decline in earnings following job loss. Using detailed skill requirements from the near universe of online vacancies, we estimate technological change by occupation and find that technological change accounts for 45 percent of the decline in earnings after job loss. Technological change lowers earnings after job loss by requiring workers to have new skills to perform newly created jobs in their prior occupation. When workers lack the required skills, they move to occupations where their skills are still employable but are paid a lower wage.

This paper shows that more highly concentrated labour markets experience more positive employment effects of the minimum wage. In the most concentrated labour markets, employment rises following a minimum wage increase. The paper establishes its main findings by studying the effects of local minimum wage increases on a key low-wage retail sector, and using data on labour market concentration that covers the entirety of the U.S. with fine spatial variation at the occupation level. The results carry over to the fast-food sector and the entire low-wage labour market and are robust to using proxies of labour market concentration available for a broader range of industries, such as the number of establishments and population density. A model of oligopsonistic competition can explain these effects: there is more room to increase wages in high-concentration areas where wages tend to be further below marginal productivity. These findings provide evidence supporting monopsonistic wage setting as an explanation for the near-zero minimum wage employment effect documented in prior work.