Ian Ayres

Yale Law School
P.O. Box 208415
New Haven, CT 06520-8415
Tel: 203/432-7101
Fax: 203/432-8095

E-Mail: EmailAddress: hidden: you can email any NBER-related person as first underscore last at nber dot org
NBER Program Affiliations: LE
NBER Affiliation: Research Associate
Institutional Affiliation: Yale University

NBER Working Papers and Publications

September 2009Evidence from Two Large Field Experiments that Peer Comparison Feedback Can Reduce Residential Energy Usage
with Sophie Raseman, Alice Shih: w15386
By providing feedback to customers on home electricity and natural gas usage with a focus on peer comparisons, utilities can reduce energy consumption at a low cost. We analyze data from two large-scale, random-assignment field experiments conducted by utility companies providing electricity (the Sacramento Municipal Utility District (SMUD)) and electricity and natural gas (Puget Sound Energy (PSE)), in partnership with a private company, Positive Energy/oPower, which provides monthly or quarterly mailed peer feedback reports to customers. We find reductions in energy consumption of 1.2% (PSE) to 2.1% percent (SMUD), with the decrease sustained over time (seven months (PSE) and twelve months (SMUD)).

Published: Evidence from Two Large Field Experiments that Peer Comparison Feedback Can Reduce Residential Energy Usage, 29 JOURNAL OF LAW, ECONOMICS AND ORGANIZATION 992 (2013) (with Sophie Raseman & Alice Shih).

June 2008Life-cycle Investing and Leverage: Buying Stock on Margin Can Reduce Retirement Risk
with Barry J. Nalebuff: w14094
This paper is no longer available on-line from the NBER. A revised version of the paper has been published as "Diversification Across Time" in the Journal of Portfolio Management 39 (Winter 2013), pp.73-86.

Published: Hardcover: 240 pages Publisher: Basic Books (May 4, 2010) Language: English ISBN-10: 0465018297 ISBN-13: 978-0465018291

November 2002Shooting Down the More Guns, Less Crime Hypothesis
with John J. Donohue III: w9336
John Lott and David Mustard have used regression analysis to argue forcefully that 'shall-issue' laws (which give citizens an unimpeded right to secure permits for concealed weapons) reduce violent crime. While certain facially plausible statistical models appear to generate this conclusion, more refined analyses of more recent state and county data undermine the more guns, less crime hypothesis. The most robust finding on the state data is that certain property crimes rise with passage of shall- issue laws, although the absence of any clear theory as to why this would be the case tends to undercut any strong conclusions. Estimating more statistically preferred disaggregated models on more complete county data, we show that in most states shall- issue laws have been associated with more ...

Published: Ayres, Ian and John J. Donohue III. "Shooting Down the More Guns, Less Crime Hypothesis." 55 Stanford Law Review 1193 (2003).

February 1997Measuring Positive Externalities from Unobservable Victim Precaution: An Empirical Analysis of Lojack
with Steven D. Levitt: w5928
Private expenditures on crime reduction have potentially important externalities. Observable measures such as barbed-wire fences and deadbolt locks may shift crime to those who are unprotected, imposing a negative externality. Unobservable precautions, on the other hand, may provide positive externalities since criminals cannot determine a priori who is protected. Focusing on one specific form of victim precaution, Lojack, we provide the first thorough empirical analysis of the magnitude of such externalities. Because installing Lojack does not reduce the likelihood that an individual car will be stolen, any decrease in the aggregate crime rates due to Lojack is an externality from the perspective of the individual Lojack purchaser. We find that the presence of Lojack is associated wi...

Published: Quarterly Journal of Economics, Vol. 108, no. 1 (February 1998): 43- citation courtesy of

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