各校計畫成果

活動簡介

Prof. Kuan-Ming Chen participate in research “Reservation Wages and Workers’ Valuation of Job Flexibility: Evidence from a Natural Field Experiment.”The paper has been conditionally accepted by the Journal of the European Economic Association. In this paper, we quantify how labor supply elasticities and reservation wages vary be- tween people and over time, and infer workers’ valuation of flexibility in their choices of work hours. Economists and policymakers are keenly interested in these quantities, especially lately with the growth in jobs that offer flexible work schedules. Our study takes advantage of a large natural field experiment at Uber, the largest ride-sharing company. Combining this experiment with high frequency panel data on wages and individual work decisions, we estimate a dynamic labor supply model that let us re- cover reservation wages, labor supply elasticities, and workers’ valuation of flexibility. We also show the biases in reservation wages and labor supply elasticities that arise if one uses observational data on wages or a static labor supply model.

We illustrate the impact of the GSL experiment (an experiment that randomly increases the guaranteed surge levels for drivers) on drivers' labor supply responses before, during, and after the experiment period in the figure. These effects are shown by the solid lines, while the dotted lines depict the changes in wages resulting from the GSL experiment. We observe significant shifts in labor supply during the experiment period. Specifically, during this time, treated drivers increase their employment rate per hour and total hours worked by about one percent compared to the control group. There is also some indicative evidence of lasting effects beyond the experiment period. For instance, in the hour following the experiment, labor supply for the treated group remains half a percent higher than that of the control group.

Notes: In this figure, taken from Chen et al. (forthcoming), we illustrate the changes in the probability of working and minutes worked. The estimation is performed separately for the first half (Exp 1) and the second half (Exp 2) of the experiment windows. On average, the experiment windows last 5.2 hours. The shaded area in the figure indicates the experiment hours with the GSL switched on. The solid line represents the difference in labor supply responses, and the dashed line represents the difference in predicted hourly wages.