NBER Publications by Mark F. Stehr

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Working Papers and Chapters

November 2012Incentives, Commitments and Habit Formation in Exercise: Evidence from a Field Experiment with Workers at a Fortune-500 Company
with Heather Royer, Justin R. Sydnor: w18580
Financial incentives have been shown to have strong positive short‐run effects for problematic health behaviors, but the effects often disappear once incentive programs end. This paper analyzes the results of a large‐scale workplace field experiment to examine whether self‐funded commitment contracts improve the long‐run effects of incentive programs. Consistent with existing findings, workers responded strongly to an incentive targeting use of the company gym, but long‐run effects were modest, at best. However, workers in the treatment arm that combined the incentive program with a commitment contract option showed long‐lasting behavioral changes, persisting even 1 year after the incentive ended.
January 2010Intended and Unintended Effects of Youth Bicycle Helmet Laws
with Christopher S. Carpenter: w15658
Over 20 states have adopted laws requiring youths to wear a helmet when riding a bicycle. We confirm previous research indicating that these laws reduced fatalities and increased helmet use, but we also show that the laws significantly reduced youth bicycling. We find this result in standard two-way fixed effects models of parental reports of youth bicycling, as well as in triple difference models of self-reported bicycling among high school youths that explicitly account for bicycling by youths just above the helmet law age threshold. Our results highlight important intended and unintended consequences of a well-intentioned public policy.

Published: “Intended and Unintended Consequences of Youth Bicy cle Helmet Laws” Christopher Carpenter and Mark Stehr, Journal of Law and Economics (2011) 54(2): 305-324.

September 2007The Effects of Mandatory Seatbelt Laws on Seatbelt Use, Motor Vehicle Fatalities, and Crash-Related Injuries among Youths
with Christopher S. Carpenter: w13408
We provide the first comprehensive assessment of the effects of mandatory seatbelt laws on self-reported seatbelt use, highway fatalities, and crash-related injuries among high school age youths using data from the Centers for Disease Control's (CDC) national, state, and local Youth Risk Behavior Surveys (YRBS) and the Fatality Analysis Reporting System (FARS) from 1991 to 2005, a period spanning over 20 changes in state seatbelt laws. Our quasi-experimental approaches isolate the independent effects of seatbelt laws net of demographic characteristics, area and year fixed effects, and smooth area-specific trends. Across all data sources, we find consistent evidence that state mandatory seatbelt laws -- particularly those permitting primary enforcement -- significantly increased seatbelt ...

Published: Carpenter, Christopher S. & Stehr, Mark, 2008. "The effects of mandatory seatbelt laws on seatbelt use, motor vehicle fatalities, and crash-related injuries among youths," Journal of Health Economics, Elsevier, vol. 27(3), pages 642-662, May. citation courtesy of

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