Notes: These labor supply elasticities were obtained by estimating Equations 9–11, on a pooled sample of all (dominant) employment spells. Each model contains age, age-squared, and indicator variables for female, nonwhite, Hispanic, high school diploma, some college, college degree or greater, state-by-year, and each of 20 NAICS sectors. The second column restricts the sample to only those firms for which afirm-specific elasticity can be estimated (described in detail in Section IV). The third and fourth columns display the results when firm and individual heterogeneity are accounted for in each stage of the estimation process (for example, stratified proportional hazard models and conditional logits). For computational reasons (due mainly to the nonlinear nature of these models), a specification that controls for both firm and individual heterogeneity could not be estimated.