Declared-Strategy Voting

I completed my Doctor of Science degree in Engineering and Policy at Washington University in St. Louis. My dissertation research focussed on a new type of voting system called declared-strategy voting. My advisor, Dr. Ron Cytron, is continuing to work in this area with other students.

What exactly is declared-strategy voting? The short answer: DSV is a novel group decision-making procedure in which preference is specified using voting strategies, thus allowing voters to cast ballots that are both effective and expressive. For a simple illustration, consider the dilemma faced by Perot supporters in the 1992 US Presidential election: vote honestly (expressively) and waste their votes, or vote effectively (for a second choice) and forfeit the opportunity to express their true preferences. In a DSV election voters indicate their (honest) preference for each candidate on a numeric scale. The optimal strategy is then generated for each voter based on their expressed preferences and the preferences of the other voters. So, if it turns out that Perot really has a decent chance of winning, voters who give Perot their highest rating will have their votes cast for Perot. But if it turns out that Perot has a slim chance of winning, these voters might have their vote cast for a second choice, depending on how highly they rated the other candidates. While DSV could certainly be applied to national elections as in this example, it has more likely application in other types of decision-making situations where a group must choose between many alternatives. It also may be useful to policy-makers who use survey data to guide their decisions.

Want to learn more? I recommend the following publications, the most comprehensive of which is my dissertation. I've included abstracts below. See also Ron Cytron's Declared Strategy Voting Simulator and restaurant selection example.

Declared-Strategy Voting: An Instrument for Group Decision-Making Washington University Dissertation. December 1996.

Towards an Information-Neutral Voting Scheme That Does Not Leave Too Much to Chance. Paper presented at the Midwest Political Science Association Annual Meeting, April 18-20, 1996 (with R. Cytron).

Can Declared Strategy Voting be an Effective Instrument for Group Decision-Making? Washington University technical report WUCS-95-04. January 1995. (A technical report version of my dissertation proposal. A lot has changed since then.)
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Abstracts

Declared-Strategy Voting: An Instrument for Group Decision-Making

The goal of this research is to determine whether declared-strategy voting (DSV) can be an effective tool for group decision-making. DSV is a novel group decision-making procedure in which preference is specified using voting strategies--first-order mathematical functions that specify a choice in terms of zero or more parameters. Three ideas motivate DSV: the possibility of taking advantage of electronic voting systems to achieve more beneficial methods of vote aggregation than are feasible with traditional voting systems, the desire to find an information-neutral voting system, and the desire to maximize a voting system's expressiveness. We present designs for two types of DSV systems: batch DSV and ballot-by-ballot DSV. We also develop a rational-strategy formulator that can determine optimal strategies for each voter given only the voter's cardinal utilities for each alternative. Our strategy formulator is based on the expected-utility model of voting and employs a novel technique for calculating pivot probabilities. We present the results of a DSV acceptability study as well as DSV simulations of several types of voting situations.

DSV may be applied to group decision-making situations in which a policy-maker must make a decision using a non-binding survey as a guide, as well as to situations in which a large or small group must make a decision through a binding vote. We demonstrate that DSV can help a decision-maker analyze group preferences. DSV is useful for gauging strength of preference and level indifference, identifying sets of alternatives that act as mutual substitutes, and determining which alternatives voters would support if they knew their favorite was not a serious contender. We also show that DSV can be effective as a voting system. DSV allows voters to vote strategically, maximizing the effectiveness of their votes regardless of whether they have obtained information about the preferences of the rest of the voters or whether they know how to formulate optimal strategies. DSV also allows voters to express their sincere preferences, including preference intensities, without sacrificing the effectiveness of their votes.


Towards an Information-Neutral Voting Scheme That Does Not Leave Too Much to Chance

We examine a new voting procedure that allows voters to express their preferences in the form of a voting strategy -- a first-order function which specifies a vote. We examine the calculations necessary to formulate such voting strategies, and present examples which illustrate the effects of risk. The voting framework we discuss allows rational voters to vote strategically using decision-theoretic techniques to select their optimal strategies, even if they have no prior information about the preferences of others and are unfamiliar with decision theory; moreover, randomness can be introduced into the framework to increase resistance to manipulability while maintaining outcomes that do not leave too much to chance.


Can Declared Strategy Voting be an Effective Instrument for Group Decision-Making?

The goal of this research is to determine whether declared strategy voting can be an effective tool for group decision-making. Declared strategy voting is a novel group decision-making procedure in which preference is specified using voting strategies -- first-order mathematical functions that specify a choice in terms of zero or more parameters. This research will focus on refining the declared strategy voting concept, developing an accessible implementation of declared strategy voting that can be used for mock elections, assessing the potential impacts of declared strategy voting, and evaluating the effectiveness of declared strategy voting for group decision-making. This proposal describes the significance of this research, preliminary studies, and proposed methodology for the remainder of this project.

Lorrie Faith Cranor