NBER Publications by Ian Ayres

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)).

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.

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 ...

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...