John L. Hartman
Department of Economics
2028 North Hall
University of California, Santa Barbara
Mail Code 9210
Santa Barbara, CA 93106
NBER Working Papers and Publications
|January 2011||Letting Down the Team? Evidence of Social Effects of Team Incentives|
with Philip Babcock, Kelly Bedard, Gary Charness, Heather Royer: w16687
This paper estimates social effects of incentivizing people in teams. In two field experiments featuring exogenous team formation and opportunities for repeated social interactions, we find large team effects that operate through social channels. The team compensation system induced agents to choose effort as if they valued a marginal dollar of compensation for their teammate from two-thirds as much (in one study) to twice as much as they valued a dollar of their own compensation (in the other study). We conclude that social effects of monetary team incentives exist and can induce effort at lower cost than through direct individual payment.
|December 2010||Networks and Workouts: Treatment Size and Status Specific Peer Effects in a Randomized Field Experiment|
with Philip S. Babcock: w16581
This paper estimates treatment size and status specific peer effects that are not detected by widely-used approaches to the estimation of spillovers. In a field experiment using university students, we find that subjects who have been incentivized to exercise increase gym usage more if they have more treated friends. However, control subjects are not influenced by their peers. Findings demonstrate that fraction treated has a large influence on outcomes in this environment, and spillovers vary greatly by treatment status. Results highlight subtle effects of randomization and document a low-cost method for improving the generalizability of controlled interventions in networked environments.