This study establishes empirically a positive but nonlinear relationship between weekly hours and hourly wage growth. For workers who put in over 47 hours per week, 5 extra hours are associated with a 1% increase in annual wage growth. This correlation is not present when hours are lower. The relationship is especially strong for young professionals. Data on promotions provide evidence in support of a job-ladder model that combines higher skill sensitivity of output in higher-level jobs with heterogeneous preferences for leisure. The results can be used to account for part of the gender wage gap.

We introduce the idea that easily inferable demographic characteristics such as gender may not be sufficient to define type in the supervisor-employee mentoring relationship. We use longitudinal data on athletic directors at NCAA Division I programs to identify through observed mobility the propensity of top-level administrators to hire and retain female head coaches, above and beyond an organization's culture. We show that supervisor gender appears to be unrelated to female friendliness in this setting. Overall, our findings indicate that more focus should be placed on the more complex manager type defined by attitudes in addition to attributes.

Investigating Income Effects in Scanner Data: Do Gasoline Prices Affect Grocery Purchases? by Dora Gicheva, Justine Hastings and Sofia Villas-Boas. Published in volume 100, issue 2, pages 480-84 of American Economic Review, May 2010