An undervote occurs when the number of distinct choices selected by a voter in a contest is less than the maximum number allowed for that contest or when no selection is made for a single choice contest. In a contested election, an undervote can be construed as active voter disaffection: a voter engaged enough to cast a vote without the willingness to give the vote to any candidate. An undervote can be intentional for purposes including

protest vote A protest vote (also called a blank, null, spoiled, or "none of the above" vote) is a vote cast in an election to demonstrate dissatisfaction with the choice of candidates or the current political system. Protest voting takes a variety of forms a ...

tactical voting Strategic voting, also called tactical voting, sophisticated voting or insincere voting, occurs in voting systems when a voter votes for another candidate or party than their ''sincere preference'' to prevent an undesirable outcome. For example, ...

, or abstention. Alternately undervotes can be unintentional and caused by many factors including poor

ballot design A ballot is a device used to cast votes in an election and may be found as a piece of paper or a small ball used in secret voting. It was originally a small ball (see blackballing) used to record decisions made by voters in Italy around the 16t ...

. Undervotes caused by voting for a single candidate in multiple positions is usually caused by a voter's misunderstanding of the mechanics of the preference ballot. Undervotes combined with

overvote An overvote occurs when one votes for more than the maximum number of selections allowed in a contest. The result is a spoiled vote which is not included in the final tally. One example of an overvote would be voting for two candidates in a single ...

s (known as

residual vote In voting, a ballot is considered spoilt, spoiled, void, null, informal, invalid or stray if a law declares or an election authority determines that it is invalid and thus not included in the vote count. This may occur accidentally or deliberat ...

s) can be an academic indicator in evaluating the accuracy of a voting system when recording

voter Voting is a method by which a group, such as a meeting or an electorate, can engage for the purpose of making a collective decision or expressing an opinion usually following discussions, debates or election campaigns. Democracies elect holde ...

intent.

References

External links

Champaign County Illinois November 2006 Undervote Analysis

Caltech/ MIT Voting Technology Project
Elections Voting theory {{election-stub