Research
Below, I provide links to and abstracts from selected papers.
A DODGSON-HARE SYNTHESIS
Constitutional Political Economy 34:3, September 2023
Abstract: In 1876, Charles Dodgson (better known as Lewis Carroll) proposed a committee election procedure that chooses the Condorcet winner when one exists, and otherwise eliminates candidates outside the Smith set, then allows for re-votes until a Condorcet winner emerges. The present paper discusses Dodgson’s work in the context of strategic election behavior and suggests a “Dodgson-Hare” method: a variation on Dodgson’s procedure for use in public elections, which allows for candidate withdrawal and employs Hare’s plurality-loser-elimination method to resolve the most persistent cycles. Given plausible (but not unassailable) assumptions about how candidates decide to withdraw in the case of a cycle, Dodgson-Hare outperforms Hare, Condorcet-Hare, and 12 other voting rules in a series of spatial-model simulations which count how often each rule is vulnerable to coalitional manipulation. In the special case of a one-dimensional spatial model, all coalitional voting strategies that are possible under Condorcet-Hare can be undone in Dodgson-Hare, by the withdrawal of candidates who have incentive to withdraw.
Click here for the appendix.
SELECTING THE RUNOFF PAIR
With Nicolaus Tideman. Public Choice 182, January 2020
Abstract: Although two-round voting procedures are common, the theoretical voting literature rarely discusses any such rules beyond the traditional plurality runoff rule. Therefore, using four criteria in conjunction with two data-generating processes, we define and evaluate nine “runoff pair selection rules” that comprise two rounds of voting, two candidates in the second round, and a single final winner. The four criteria are: social utility from the expected runoff winner (UEW), social utility from the expected runoff loser (UEL), representativeness of the runoff pair (Rep), and resistance to strategy (RS). We examine three rules from each of three categories: plurality rules, utilitarian rules and Condorcet rules. We find that the utilitarian rules provide relatively high UEW and UEL, but low Rep and RS. Conversely, the plurality rules provide high Rep and RS, but low UEW and UEL. Finally, the Condorcet rules provide high UEW, high RS, and a combination of UEL and Rep that depends which Condorcet rule is used.
Click here for the supplemental appendix.
PROGRESSIVE AND REGRESSIVE EQUILIBRIA IN A TAX COMPETITION GAME
Public Finance Review 45, May 2017
Abstract:
This paper models inter-jurisdictional competition over non-linear taxes on the incomes of mobile individuals. Each individual has exogenous wealth and a location preference that is drawn from a continuous distribution. We find that more concave utility of consumption functions lead to more progressive tax structures, as richer people place less value on marginal consumption relative to location. In the benchmark model, a relative risk aversion coefficient of one is the boundary between progressivity and regressivity. The exercise helps us to understand which types of jurisdictions are more likely to have progressive taxes as their optimal policies.
STATISTICAL EVALUATION OF VOTING RULES
With Nicolaus Tideman and Rafael Cosman. Social Choice and Welfare 46, January 2016
Abstract:
We generate synthetic elections using Polibarometer survey data, ANES survey data, a spatial model, an IAC model, and an IC model. For each election, we test whether each of 54 voting rules is (1) non-manipulable, and (2) efficient in the sense of maximizing summed thermometer scores. We find that Hare and Condorcet-Hare are the most strategy-resistant non-dictatorial rules. Most rules have very similar utilitarian efficiency scores, with the exception of a few poor performers such as random dictator, plurality and anti-plurality. Our results are highly robust across data-generating processes. In addition to presenting our numerical results, we explore analytically the effects of adding a ‘Condorcet-else’ provision to a base rule and show that, for all but a few base rules, this modification cannot introduce a possibility of manipulation where none existed before.
DIRECT VOTING AND PROXY VOTING
Constitutional Political Economy 26:2, June 2015
Abstract: I develop a hybrid of direct democracy and representative democracy in which each citizen may vote directly on each issue, or delegate his vote on any issue to a representative (that is, a proxy) of his own choosing. I construct both an axiomatic argument for such a system and an argument based on its ability to ameliorate the information problems inherent in both direct and representative democracy. I also propose practical measures for implementation, including new variations on existing proxy system proposals. These new variations include a ‘Dodgsonesque’ procedure, a proportional agenda-setting procedure, a provision for virtual committees, and a provision for continual consideration of issues.
STRATEGIC VOTING AND NOMINATION
Social Choice and Welfare 42, January 2014
Abstract: Using computer simulations based on three separate data generating processes, I estimate the fraction of elections in which sincere voting will be a core equilibrium given each of eight single-winner voting rules. Additionally, I determine how often each voting rule is vulnerable to simple voting strategies such as ‘burying’ and ‘compromising’, and how often each voting rule gives an incentive for non-winning candidates to enter or leave races. I find that Hare is least vulnerable to strategic voting in general, whereas Borda, Coombs, approval, and range are most vulnerable. I find that plurality is most vulnerable to compromising and strategic exit (causing an unusually strong tendency toward two-party systems), and that Borda is most vulnerable to strategic entry. I use analytical proofs to provide further intuition for some of my key results.
FOUR CONDORCET-HARE HYBRID METHODS FOR SINGLE-WINNER ELECTIONS
Voting Matters 29, October 2011
Abstract: This paper examines four single-winner election methods, denoted here as Woodall, Benham, Tideman, and Smith-Hare, which each make use of both Condorcet’s pairwise comparison principle and the plurality elimination principle used in Hare’s single transferable vote system. These methods have many significant properties in common, including Smith efficiency and relatively strong resistance to strategic manipulation, though they differ slightly with regard to the minor criteria of ‘Smith-IIA’ and ‘mono-add-plump’.
CARDINAL-WEIGHTED PAIRWISE COMPARISON
Voting Matters 19, November 2004
Abstract: This paper introduces a new voting method named cardinal-weighted pairwise comparison, or cardinal pairwise for short. It is based on Condorcet’s method of pairwise comparison, but in addition to asking voters to rank the candidates in order of preference, this method also asks them to rate the candidates, for example on a scale from 0 to 100. The ordinal ranking information is still used to decide the winner and loser of each pairwise comparison, but the cardinal rating information is used to decide the relative strength of the pairwise victories/defeats, which determines how majority rule cycles are resolved if they occur.
SELF-SUSTAINING PUBLIC EMPLOYMENT
Working paper
Abstract: In this paper we propose and consider a public employment program that accepts all applicants, pays each worker according to the value he adds to production, and aims to maximize worker surplus subject to a non-negative profit constraint. We construct an original model of production and compensation in which production inputs are discrete and heterogeneous, the division of surplus depends on firm objectives, and imperfect information reduces efficiency by limiting the search horizons of economic actors. In the baseline version of the model, the public employment program increases efficiency. In some alternative versions, the impact on efficiency is ambiguous. We draw on these possible sources of inefficiency when making practical suggestions for the program’s design.
Some of my pre-doctoral work on voting rules might still have reference value, such as the Survey of Basic Voting Methods. My old Alternative Voting Methods page provides an archive of this work.