Review Vocabulary

Continuous voter distribution A curve that gives, on the vertical axis, the number (or percentage) of voters who have attitudes at that point on the left-right continuum. (p. 515)

Discrete distribution of voters A distribution in which voters are located at only certain positions along the left-right continuum. (p. 509)

Electoral College A body of 538 electors that selects the U.S. president. (p. 504)

Equilibrium A pair of policy positions from which neither candidate has an incentive to depart unilaterally. (p. 511)

Extended median The equilibrium position of two candidates when there is no median. (p. 512)

Maximin position A candidate’s position in which there is no other position that can guarantee a better outcome (e.g., more votes) whatever position another candidate adopts. (p. 511)

Median The point on the horizontal axis of a voter distribution where at least half the voters have attitudes that lie to the left and half to the right. (p. 511)

Median of a continuous voter distribution The collection of points on the horizontal axis where half the area underneath the continuous voter distribution is to the left of and half is to the right of . (p. 517)

528

Median-voter theorem In a two-candidate election with an odd number of voters, the median is the unique equilibrium position. (p. 512)

Midpoint For points and on the real line, the midpoint is . (p. 509)

National Popular Vote law Proposed law that would give all the electoral votes of a state to the national popular-vote winner if states with a majority of electoral votes enact the law. (p. 524)

1/3-separation obstacle An obstacle for the entry of a third candidate, created if two previous entrants are sufficiently close together. (p. 520)

Policy position A point on a line that represents a candidate’s position on an issue in the left-right political spectrum. (p. 509)

Quota The proportion of all delegates a candidate should receive, given his or her adjusted percentage of the vote.

It is the adjusted percentage times the total number of delegates. (p. 506)

Spatial models The representation of candidate positions along a left-right continuum or in higher dimensions in order to determine the equilibrium or optimal positions of the candidates. (p. 513)

Spoiler A candidate who cannot win but “spoils” the election for a candidate who otherwise would win. (p. 523)

2/3-separation opportunity An opportunity for the entry of a third candidate, created if two previous entrants are sufficiently far apart. (p. 520)

Unimodal A distribution is unimodal if it has one peak. (p. 520)

Voter’s ideal position (or ideal point) A point on a line that represents a voter’s most preferred or ideal election outcome on an issue in the left-right political spectrum. (p. 509)

Weighted median The weighted median of with positive integer weights , respectively, is the median of the data , where appears in the list times for each . (pp. p. 525 p. 526)

Weighted median-voter theorem In a two-candidate election under the Electoral College, if each state’s median is weighted by the state’s electoral votes, then the weighted median is an equilibrium position. (p. 526)