In this paper we compare in a consistent way micro and macro labor supply elasticities: the individual elasticity is obtained from the Panel Study of Income Dynamics (PSID); the aggregate, time-series, elasticity is estimated from the exact aggregation of the individual units, each year. Our aggregation procedure relies on a life-cycle labor supply model with home production. The individual (hours per worker) elasticity has a standard low value (0.18), while the aggregate (total hours) elasticity is much larger (0.81), with most of the di¤erence due to the extensive margin, i.e. participation/employment decisions. This result conforms to a well-known stylized fact of the labor market, though we derive it as a pure aggregation e¤ect. A broader suggestion is that micro evidence is not always a reliable guidance for calibrating aggregate macroeconomic parameters.
JEL Classi…cation Codes: E13, E32, J22