Randomized experiments in criminology: What have we learned in the last two decades?

This paper aims to review randomized experiments in criminology with offending outcomes and reasonably large numbers that were published between 1982 and 2004. A total of 83 experiments are summarized, compared with only 35 published between 1957 and 1981: 12 on policing, 13 on prevention, 14 on corrections, 22 on courts, and 22 on community interventions. Randomized experiments are still relatively uncommon, but there have been more large-scale multi-site experiments and replication programs. There have also been several experiments in which 100 or more places were randomly assigned. Relatively few experiments (only 10 out of 83) were conducted outside the United States. Meta-analyses suggest that prevention methods, correctional therapy, batterer programs, drug courts, juvenile restitution and deterrent policing were effective in reducing offending, while Scared Straight and boot camp programs caused a significant increase in offending.     

Assessing Market Power: The Trade-off Between Market Concentration and Multi-Market Participation

This analysis reveals that traditional market power measuresare biased under the conditions of multi-market participationand demand interdependence. Specifically, when complementary(substitutable) demands dominate, traditional market power measuresare biased upward (downward). A similar bias carries over tothe evaluation of mergers. To wit, mergers that simultaneouslyincrease market concentration and multi-market participationcan result in lower prices even in the absence of merger economies.It follows that merger guidelines that place undue emphasison market concentration can lead policymakers to block (approve)mergers that enhance (diminish) consumer welfare.     

Situational variation in moral judgment: In a stage or on a stage?

Two issues were examined in this study—the consistency of moral judgment across different types of dilemma and different social contexts, and the relationship between the structure (stage) of moral judgment and the content of moral decisions. Forty subjects were given two hypothetical dilemmas about business decisions and two standard Kohlberg dilemmas. Half the subjects directed their responses to a business audience, half to a philosophical audience. Responses to the moral dilemmas were scored in accordance with the Colby and Kohlberg (1987) scoring manual. Stage of moral reasoning was found to be significantly higher on the Kohlberg dilemmas than on the business dilemmas. A significant interaction between type of dilemma and audience was attributed to the tendency of subjects directing their responses to a business audience to interpret one of the business dilemmas in terms of the moral order of business, but for subjects directing their responses to a philosophy audience to treat it as a philosophical dilemma. The other business dilemma evoked uniformly low-level moral judgments. The amount of selfishness intrinsic in subjects' moral choices on the business dilemmas was significantly negatively correlated with moral maturity on the business dilemmas, but not with their moral maturity on Kohlberg's test. These results are interpreted as more consistent with models of moral development such as those advanced by C. G. Levine ([1979] Stage Acquisition and Stage Use: An Appraisal of Stage Displacement Explanations of Variation in Moral Reasoning, Human Development, Vol. 22, pp. 145–164), J. Rest ([1983] Morality, in: P. H. Mussen [ed.], J. H. Flavell and E. Markman [Vol. eds.], Handbook of Child Psychology [Vol. 3, 4th ed.], John Wiley & Sons, New York), and R. Harré ([1984]) Personal Being: A Theory for Individual Psychology, Harvard University Press, Cambridge, Massachusetts), which posit a relatively wide range of within-person stage use and emphasize the determining power of social situations, than with the more constructivistic model of moral development of Colby and Kohlberg (1987).This research was supported by Grant No. 410-87-1115 from the Social Sciences and Humanities Research Council of Canada.Received B.A. and M.A from Simon Fraser University. Research interests include moral development, and the influence of social interaction and language on the development of reasoning.Received Ph.D. from Harvard University. Research interests include moral development, altruism, and self-deception.