Voter Paradox (1 Candidate)

Game Description

Back to school! Some students at MobLab U proposed a basketball club. To determine whether the club is worthwhile the faculty at MobLab U ask students to vote. Each student has a choice: Vote or Abstain. Abstention costs the student nothing. On the other hand, voting is costly because students must walk to campus to vote on Saturday. If the vote passes a minimum threshold from the student body, then the basketball club is created and each student receives 100 points. If the minimum threshold isn’t reached, each student receives 0 points.

Note: The cost of voting is incurred regardless of outcome.

Learning Objective 1: The Paradox of Voting

Voter turnout is often predicted to be low because voting is costly and voters are unlikely to be pivotal. However, voter turnout is often much higher than predicted. Explore this paradox with students.

Learning Objective 2: The Size Effect

An increase in the size of the electorate should lead to lower voter turnout.

Learning Objective 3: The Voting Cost Effect

Lowering the cost of voting improves voter turnout.

Brief Instructions

Each student receives information on their personal cost to voting, group size, and the minimum threshold of votes required for the basketball club to be created. Then students make a simultaneous decision to vote or abstain. Individual payoffs are based on the outcome of the election and whether the individual voted or abstained:

In repeated games students receive end of round feedback on their payoff and what fraction of their group voted.

Key Treatment Variations

Group Size

Increase the group size. The direct utility from voting is discounted by the probability of casting a pivotal vote. Increase group size to make the paradox of voting more evident to students and to demonstrate the size effect that turnout rates are lower in large elections.

Voting Cost

Whether the cost is drawn from a uniform distribution, or is constant across all individuals, show students that lower costs will lead to greater voter turnout.


The top of the summary screen presents aggregate group information in table form: Round, Total Number of Voters, Total Votes, Total Turnout Rates, and Winning Candidate.

Table 1: Aggregate Data

This next graph shows the vote distribution for each round, with the number of votes to pass highlighted by the dashed green line.

Graph 1: Vote Distribution

The aggregate cost distribution graph is also a multi-round summary that plots how the decision to vote or abstain is related to the cost of voting. On the x-axis are the categories Vote and Abstain and the “Cost of Voting”. On the y-axis is the number of voters with that cost. The bar graph shows the average cost to voting for people in each decision category.

Graph 2: Cost Distribution
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