Value: see subjective value.

Vanderbilt Ph.D. in law and economics: program launched at Vanderbilt University in 2006 by W. Kip Viscusi and Joni Hersch, both formerly of Harvard University. The program constitutes the first example of a Ph.D. program issued by a law school faculty in the United States. The Vanderbilt program is designed to allow students to pursue a joint J.D./Ph.D. with a focus on law and economics. The program addresses the growing interest in exploring the intersection of law and applied economics, and is a result of the growing importance and influence of the field of law and economics itself. The courses are taught by a combination of law, economics, and business professors and are open to students in the law, economics, and business programs. Students complete coursework in microeconomic theory, econometrics, and law and economics theory. As is often the case, the principal fields for upper-level concentrations are dictated by the research specialties of the teaching faculty, and currently include behavioral law and economics, labor and human resources, and risk and environmental regulation. See also EDLE, EMLE, and Erasmus program in law and economics.

Variable-sum games: unlike zero-sum and constant-sum games, variable-sum games are characterized by a variable aggregate payoff, either positive (positivesum games) or negative (negative-sum games). Many economic and legally relevant situations can be described as variable-sum games, in which the interaction among parties can create a gain or avoid a loss through the players’ coordination or cooperation. For policymakers seeking to maximize aggregate social welfare, variable-sum games will be the only relevant form of interaction since the aggregate welfare in a constant-sum game will be constant and “maximization” will be trivially satisfied regardless of the choice of policy – or, indeed, the players’ moves. Examples range from contract rules used to foster efficient bargains (positive-sum game) or procedural rules used to discourage inefficient litigation (negative-sum game). See also constant-sum games, zero-sum games, and inessential games.