fying a well-fitting model with existing data and statistical methods.7 In summary, the problems posed by high-dimensional estimation, misspecified models, and lack of knowledge of the correct set of explanatory variables seem insurmountable with observational data.


Ayers, I., and J.J. Donohue 1999 Nondiscretionary concealed weapons law: A case study of statistics, standards of proof, and public policy. American Law and Economics Review 1:436.

Black, D.A., and D.S. Nagin 1998 Do right-to-carry laws deter violent crime? Journal of Legal Studies 27:209-219.

Bronars, S., and J.R. Lott, Jr. 1998 Criminal deterrence, geographic spillovers, and the right to carry concealed handguns. American Economic Review 88:475-479.

Donohue, J.J. 2002 Divining the Impact of State Laws Permitting Citizens to Carry Concealed Handguns. Unpublished manuscript, Stanford Law School.

Härdle, W. 1990 Applied Nonparametric Regression. Cambridge: Cambridge University Press.

Lott, J.R. 2000 More Guns, Less Crime: Understanding Crime and Gun-Control Laws. Chicago: University of Chicago Press.

Lott, J.R., and D.B. Mustard 1997 Crime, deterrence, and right-to-carry concealed handguns. Journal of Legal Studies 26(1):1-68.

Ramsey, J.B. 1969 Tests for specification errors in classical linear least squares regression analysis. Journal of the Royal Statistical Society Series B 31(2):350-371.

Tucker, W. 1987 Where do the homeless come from? National Review Sept. 25:32-43.


Much current research in statistics and econometrics is directed at “dimension reduction.” This consists of imposing shape assumptions that are much weaker than those of models like 6.1 and 6.2 but strong enough to reduce the effective number of shapes that must be considered and thereby to increase estimation precision substantially. Although these techniques show considerable promise, they have not yet been developed sufficiently to be applicable to problems like estimation of the effects of right-to-carry laws.

The National Academies of Sciences, Engineering, and Medicine
500 Fifth St. N.W. | Washington, D.C. 20001

Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement