An axiomatic theory of political representation

We discuss the theory of gerrymandering-proof voting rules. Our approach is axiomatic. We show that, for votes over a binary set of alternatives, any rule that is unanimous, anonymous, and gerrymandering-proof must decide a social outcome as a function of the proportions of agents voting for each alternative, and must either be independent of this proportion, or be in one-to-one correspondence with the proportions. In an extended model in which the outcome of a vote at the district level can be a composition of a governing body (with two possible parties), we discuss the quasi-proportional rules (characterized by unanimity, anonymity, gerrymandering-proofness, strict monotonicity, and continuity). We show that we can always (pointwise) approximate a single-member district quota rule with a quasi-proportional rule. We also discuss a more general environment, where there may be more than two parties.     

Priorities in the location of multiple public facilities

A collective decision problem is described by a set of agents, a profile of single-peaked preferences over the real line and a number of public facilities to be located. We consider public facilities that do not suffer from congestion and are non-excludable. We characterize the class of rules satisfying Pareto-efficiency, object-population monotonicity and sovereignty. Each rule in the class is a priority rule that selects locations according to a predetermined priority ordering among “interest groups”. We characterize the subclasses of priority rules that respectively satisfy anonymity, avoid the no-show paradox, strategy-proofness and population-monotonicity. In particular, we prove that a priority rule is strategy-proof if and only if it partitions the set of agents into a fixed hierarchy. Any such rule can also be viewed as a collection of generalized peak-selection median rules, that are linked across populations, in a way that we describe.     

On the self-interested use of equity in international climate negotiations

We discuss self-interested uses of equity arguments in international climate negotiations. Using unique data from a world-wide survey of agents involved in international climate policy, we show that the perceived support of different equity rules by regions may be explained by the ranking of their economic costs. Despite being self-interested, equity arguments may be perceived as being used for different reasons, for example, out of fairness considerations or in order to facilitate negotiations. Consistent with experimental and behavioral studies on fairness perceptions, we find that individuals are more likely to state reasons with positive attributes if they evaluate their own region or regions that support the individual's personally preferred equity rule. Negotiators perceive the use of equity by regions as less influenced by pressure from interest groups.     

STRATEGIC CANDIDACY AND SINGLE‐PEAKEDNESS*

In elections, the voting outcomes are affected by strategic entries of candidates. We study a class of voting rules immune to strategic candidacy. Dutta et al. (2001 ) show that such rules satisfying unanimity are dictatorial if all orderings of candidates are admissible for voters’ preferences. When voters’ preferences are single‐peaked over a political spectrum, there exist non‐dictatorial rules immune to strategic candidacy. An example is the rule selecting the m‐th peak from the left among the peaks of voters’ preferences, where m is any natural number no more than the number of voters. We show that immunity from strategic candidacy with basic axioms fully characterizes the family of the m‐th leftmost peak rules.     

Individual versus group strategy-proofness: When do they coincide?

A social choice function is group strategy-proof on a domain if no group of agents can manipulate its final outcome to their own benefit by declaring false preferences on that domain. There are a number of economically significant domains where interesting rules satisfying individual strategy-proofness can be defined, and for some of them, all these rules turn out to also satisfy the stronger requirement of group strategy-proofness. We provide conditions on domains guaranteeing that for all rules defined on them, individual and group strategy-proofness become equivalent. We also provide a partial answer regarding the necessity of our conditions.     

Group identification with (incomplete) preferences

We consider the problem of identifying members of a group based on individual opinions. Since agents do not have preferences in the model, properties of rules that concern preferences (e.g., strategy‐proofness and efficiency) have not been studied in the literature. We fill this gap by working with a class of incomplete preferences derived directly from opinions. Our main result characterizes a new family of group identification rules, called voting‐by‐equitable‐committees rules, using two well‐known properties: strategy‐proofness and equal treatment of equals. Our family contains as a special case the consent rules (Samet & Schmeidler. J. Econ. Theory, 110 (2003), pp. 213–233), which are symmetric and embody various degrees of liberalism and democracy; and it also includes dictatorial and oligarchic rules that value agents’ opinions differently. In the presence of strategy‐proofness, efficiency turns out to be equivalent to non‐degeneracy (i.e., any agent may potentially be included or excluded from the group). This implies that a rule satisfies strategy‐proofness, efficiency, and equal treatment of equals if, and only if, it is a non‐degenerate voting‐by‐equitable‐committees rule.     

Time-consistent policies

In many cases the optimal open-loop policy to influence agents who solve dynamic problems is time inconsistent. We show how to construct a time-consistent open-loop policy rule. We also consider an additional restriction under which the time-consistent open-loop policy is stationary. We use examples to illustrate the properties of these tax rules.     

Conditional preferences and updating

This paper axiomatizes updating rules for preferences that are not necessarily in the expected utility class. Two sets of results are presented. The first is the axiomatization of conditional preferences. The second consists of the axiomatization of three updating rules: the traditional Bayes rule, the Dempster-Shafer rule, and the generalized Bayes rule. The last rule can be regarded as the updating rule for the multi-prior expected utility (Gilboa and Schmeidler, J. Math. Econom. 18 (1989) 141). Operationally, it is equivalent to updating each prior by the traditional Bayes rule.     

The communication requirements of social choice rules and supporting budget sets

The paper examines the communication requirements of social choice rules when the (sincere) agents privately know their preferences. It shows that for a large class of choice rules, any minimally informative way to verify that a given alternative is in the choice rule is by verifying a “budget equilibrium”, i.e., that the alternative is optimal to each agent within a “budget set” given to him. Therefore, any communication mechanism realizing the choice rule must find a supporting budget equilibrium. We characterize the class of choice rules that have this property. Furthermore, for any rule from the class, we characterize the minimally informative messages (budget equilibria) verifying it. This characterization is used to identify the amount of communication needed to realize a choice rule, measured with the number of transmitted bits or real variables. Applications include efficiency in convex economies, exact or approximate surplus maximization in combinatorial auctions, the core in indivisible-good economies, and stable many-to-one matchings.     

Determinants of compliance with fiscal rules: Misplaced efforts or hidden motivations?

This paper empirically examines which factors have influenced numerical compliance with fiscal rules in Latin American and Caribbean countries over the period 2000 to 2020. We use logistic regression models to associate three groups of specific factors with a greater or lesser probability of compliance with the rule: the macroeconomic and political environment of the countries and the design features of the enforced rules. We find that only changes in the macroeconomic and political context affect the probability of compliance with the enforced rules. In contrast, the institutional design of the fiscal rules does not seem to play an essential role in the compliance outcome. This result suggests that adjustments in this direction are not decisive for rule compliance.     

How real people make long-term decisions: The case of retirement preparation

Large variations in retirement wealth are common, with some households accumulating hundreds of thousands of dollars and others accumulating next to nothing. We examine to what extent formal planning or simple rules of thumb contribute to these differences in wealth accumulation. In particular, we investigate whether those who follow simple rules of thumb or those who come up with more complete plans accumulate more wealth than those who take an unsystematic approach. We test this empirically using a specifically designed survey about retirement preparation. We find that people who rely on a rule of thumb behave like literal planners. However, people without any systematic approach save substantially less. Our results, taken together with evidence from psychology, suggest that financial planning advice based on simple rules of thumb may be helpful for those who currently take no systematic approach.     

Allocation rules for land division

This paper studies the classical land division problem formalized by Steinhaus (Econometrica 16 (1948) 101-104) in a multi-profile context. We propose a notion of an allocation rule for this setting.  We discuss several examples of rules and properties they may satisfy. Central among these properties is division independence: a parcel may be partitioned into smaller parcels, these smaller parcels allocated according to the rule, leaving a recommended allocation for the original parcel. In conjunction with two other normative properties, division independence is shown to imply the principle of utilitarianism.     

General allocation problems with single-peaked preferences: path-independence and related topics

We face the problem of allocationg a fixed amount of a perfectly divisible good among a group of agents with single-peaked preferences. We survey the three different cases studied in the literature: the pure distribution case, the redistribution case, and the gerneral case. The so called general case provide with a natural framework to analyze the idea of path-independence. In this framework, we explore the existence of rules fulfilling this property. Our first result is negative: a strong version of this property cannot be fulfilled together with efficiency. Nonetheless, some restricted versions of the path-independence property are compatible with interesting properties, in particular no manipulability, and no envy. We then identify two solutions satisfying this sort of property: the equal distance rule, and a new extension of the uniform rule.     

A K% MONEY GROWTH LEADERSHIP RULE IN AN INTERNATIONAL MONETARY POLICY GAME

This paper examines a version of the Friedman k% money growth rule in an open economy monetary policy game. Using the two-country model proposed by Canzoneri and Henderson (1991), we show that, in response to asymmetric aggregate demand shocks, the Pareto-efficient outcome can be achieved by a policy that we call a k% money growth leadership rule. Following that rule, one country, the leader, sets her money supply growth rate, and the follower sets her money supply growth rate so as to keep the sum of nominal money supply growth at k%. We show that this policy yields the same outcome as does cooperative equilibrium. We also show that alternative policy rules, such as keeping exchange-rate adjusted money supply growth at k%, or forming a currency union, will not lead to the Pareto-efficient outcome in response to these demand shocks. ( JEL E5, F3)     

The Disunity of Unanimity

Unanimity is the optimal voting rule in a world of zero transactions costs, when side payments are impossible. When side payments are available and transactions costs are zero, the voting rule is irrelevant to the ultimate outcome. In the more realistic situation where side payments are allowed but transactions costs are positive, a unanimity voting rule creates situations where the collective choice may fail a proposed measure even if all members favor the measure in principle. This evidences a disunity between unanimity rules and unanimous outcomes. Constitutional design should focus on rules leading to unanimous outcomes, as opposed to unanimity rules.     

On the informational efficiency of simple scoring rules

We study information aggregation in large elections. With two candidates, efficient information aggregation is possible (e.g., Feddersen and Pesendorfer [5], [6] and [7]). We show that this result does not extend to elections with more than two candidates. We study a class of simple scoring rules in voting games with Poisson population uncertainty and three candidates. No simple scoring rule aggregates information efficiently, even if preferences are dichotomous and a Condorcet winner always exists. We introduce a weaker criterion of informational efficiency that requires a voting rule to have at least one efficient equilibrium. Only approval voting satisfies this criterion.     

Implementation of college admission rules

Summary We consider both Nash and strong Nash implementation of various matching rules for college admissions problems. We show that all such rules are supersolutions of the stable rule. Among these rules the lower bound stable rule is implementable in both senses. The upper bound Pareto and individually rational rule is strong Nash implementable yet it is not Nash implementable. Two corollaries of interest are the stable rule is the minimal (Nash or strong Nash) implementable solution that is Pareto optimal and individually rational, and the stable rule is the minimal (Nash or strong Nash) implementable extension of any of its subsolutions.We wish to thank Professor William Thomson for his efforts in supervision as well as his useful suggestions. We are grateful to the participants in his reading class, workshops at Bilkent University, University of Rochester, and in particular Jeffrey Banks, Stephen Ching, Bhaskar Dutta, Rangarajan Sundaram and an anonymous referee for their helpful comments.     

Fiscal rules of income transformation

Summary. The purpose of this paper is to characterize the class of fiscal rules of income transformation which are equity improving and, at the same time, preserve the ranking of existing distributions. Contrary to the related literature individual well-being depends not just on income but also on prices. We show that, when the environment is restricted such that a general transformation class still can be defined, the only “desirable” fiscal rule is the simple redistributive linear taxation schedule, of the same type that is the rule in practice in most economies. Received: May 8, 1997; revised version: September 15, 1997     

A characterization of consistent collective choice rules

We characterize a class of collective choice rules such that collective preference relations are consistent. Consistency is a weakening of transitivity and a strengthening of acyclicity requiring that there be no cycles with at least one strict preference, which excludes the possibility of a “money pump.” The properties of collective choice rules used in our characterization are unrestricted domain, strong Pareto, anonymity and neutrality. If there are at most as many individuals as there are alternatives, the axioms provide an alternative characterization of the Pareto rule. If there are more individuals than alternatives, however, further rules become available.     

Public debt rule breaking by time-inconsistent voters

This study considers how present-biased preferences influence public debt policy when a violation of debt rules is possible. To address this issue, the study extends the framework of Bisin, Lizzeri, and Yariv (American Economic Review 105, (2015), 1711–1737) by allowing for rule breaking with extra costs; we show that rule breaking occurs when a country exhibits a strong present bias. We further extend the model by introducing a political process for determining the debt rule, and we show that a polarization of debt rules emerges between countries with high and low degrees of present bias.