Are qualified majority rules special?

This essay provides a formal justification for qualified majority rules. Specifically, within an uncertain dichotomous choice framework, in which individual preferences are identical but actual judgments may differ, special majority rules emerge as decision rules that maximize the probability of making correct decisions. The main result specifies the optimal special majority as a function of a priori bias in favor of the status quo, ability, and size of the decision-making body. The analysis of the relationships among these three variables in generating certain common qualified majority rules is then pursued.     

Measuring majority power and veto power of voting rules

We study voting rules with respect to how they allow or limit a majority from dominating minorities: whether a voting rule makes a majority powerful and whether minorities can veto the candidates they do not prefer. For a given voting rule, the minimal share of voters that guarantees a victory to one of the majority’s most preferred candidates is the measure of majority power; and the minimal share of voters that allows the minority to veto each of their least preferred candidates is the measure of veto power. We find tight bounds on such minimal shares for voting rules that are popular in the literature and used in real elections. We order the rules according to majority power and veto power. Instant-runoff voting has both the highest majority power and the highest veto power; plurality rule has the lowest. In general, the greater is the majority power of a voting rule, the greater its veto power. The three exceptions are: voting with proportional veto power, Black’s rule and Borda’s rule, which have relatively weak majority power and strong veto power, thus providing minority protection. Our results can shed light on how voting rules provide different incentives for voter participation and candidate nomination.

     

States and PACs: The legacy of established decision rules

The growth of political action committees (PACs) and their growing role in campaign finance have led to calls for placing limits on campaign contributions by PACs. State decisions regarding whether to limit PAC contributions appear to result from established policy orientations regarding other campaign finance issues: states with a history of previous efforts to regulate campaign finances are more likely to limit PAC contributions.     

Optimal team and individual decision rules in uncertain dichotomous situations

In this paper, we consider the problem of determining the optimalteam decision rules in uncertain, binary (dichotomous) choice situations. We show that the Relative (Receiver) Operating Characteristic (ROC) curve plays a pivotal role in characterizing these rules. Specifically, the problem of finding the optimal aggregation rule involves finding a set ofcoupled operating points on the individual ROCs. Introducing the concept of a team ROC curve, we extend the method of characterizing decision capabilities of an individual decisionmaker (DM) to a team of DMs. Given the operating points of the individual DMs on their ROC curves, we show that the best aggregation rule is a likelihood ratio test. When the individual opinions are conditionally independent, the aggregation rule is a weighted majority rule, but with different asymmetric weights for the yes and no decisions. We show that the widely studied weighted majority rule with symmetric weights is a special case of the asymmetric weighted majority rule, wherein the competence level of each DM corresponds to the intersection of the main diagonal and the DM's ROC curve. Finally, we demonstrate that the performance of the team can be improved by jointly optimizing the aggregation rule and the individual decision rules, the latter possibly requiring a shift from the isolated (non-team) optimal operating point of each DM.Research supported by NSF grant #IRI-8902755 and ONR contract #N0014-90-J-1753.     

Do supermajority rules limit or enhance majority tyranny? evidence from the US States, 1960–1997

Buchanan and Tullock (1962) demonstrates that supermajority rules can reduce tyranny of majority problems in a democracy. However, recent theoretical work by Dixit, Grossman, and Gul (2000) postulates that this static analysis of supermajority rules may be inadequate to explain political decisions in a dynamic setting. In fact, supermajority rules may increase the incidence of majority tyranny because of rotating political representation. Using data from US state legislatures we examine the effect of supermajority rules on different categories of government expenditures and tax revenues during the latter half of the 20th century. We find supermajority rules have little effect on general government expenditures and tax revenues. However, supermajority rules are associated with lower public welfare transfers, which supports the traditional analysis of the fiscal effects of supermajority rules.     

A Talmudic constrained voting majority rule

Public Choice - Talmudic Law requires a minimal supermajority (13 out of 23) for conviction, but at the same time, provides that a unanimous conviction leads to a mistrial. We derive the necessary...     

密尔"多数暴政"思想探析——兼与《多数暴政新解》一文商榷

密尔出于对作为民主核心价值的自由与平等二者冲突的反应,看到了多数暴政的潜在威胁,提出了"多数暴政"思想.其多数暴政包括政治专制和社会专制,是指社会中的某个群体凭借数量上的优势对少数人的权利和自由的压制.密尔论述多数暴政思想的语境是代议制民主,是对托克维尔多数暴政思想的继承和发展,目的在于保护少数的权利和完善西方民主政治,这一思想不能作为分析当代中国政治的工具,但对我国政治文明与和谐社会建设具有一定的启发意义.     

Building majority coalitions for sub-majority benefit distributions

Public Choice - This paper poses a deceptively simple question. It asks, how can a program or group of programs that provides distributive benefits to recipients in a minority of legislative...     

The fairness of discounting: A majority rule approach

A model of majority rule is developed in which each of a finite number of generations votes on a redistribution of income between itself and the other generations. In voting, each generation expresses tastes for its own income and for the distribution of income across generations. The model is then used to derive the conditions under which discounting is justified — namely those conditions for which the majority rule exhibits a positive marginal rate of time preference. It is demonstrated that when each generation is wealthier than those preceding it, the parameters representing the taste for income equality must be relatively high for the majority rule to exhibit a positive marginal rate of time preference.