The National Institute of Standards and Technology (NIST) included the following definition for "Residual Vote" in the "Glossary of U.S. Voting Systems," available on its website (accessed Apr. 21, 2006):
"Total number of votes that cannot be counted for a specific contest. There may be multiple reasons for residual votes (e.g., overvotes in a contest, failure to cast ballot before leaving polling place)."
The National Academy of Sciences' 2005 report titled "Asking the Right Questions About Electronic Voting," included the following description:
"Residual vote [is] defined as the sum of overvotes and top-of-ticket undervotes (in which the voter indicates no choice for the most important contest on the ballot, and thus the ballot does not count as a vote). Overvotes are clearly errors, while undervotes are entirely legal and may reflect a voter's preference to refrain from voting in a particular contest. Nevertheless, because the top-of-ticket contest (e.g., the contest for president of the United States) is the most important contest, it is assumed that an undervote for that contest reflects an error on the part of the voter."
Charles Stewart III, PhD, Head of the Department of Political Science at the Massachusetts Institute of Technology (MIT), released a report in Feb. 2005 titled "Residual Vote in the 2004 Election," which stated:
"The residual vote...is all ballots cast that did not record a vote for president [if there is no presidential contest, this number is calculated using the contest that appears first on the ballot]. In a mechanical sense, a vote can fail to be counted either because there was no vote for president on an individual's ballot (an 'undervote') or multiple marks (an 'overvote')."
The Caltech/MIT Voting Technology Project published a report in July 2001 titled "Voting: What Is and What Could Be," which included the following description:
"Residual votes, the number of uncounted, unmarked, and spoiled ballots, provide a yardstick for measuring the effect of different machine types on the incidence of lost votes. Ballots that contribute to the residual votes are:
Uncounted ballots - Ballots that are cast by voters but uncounted by election officials for whatever reason.
Unmarked ballots - Sometimes termed the 'undervote.' May occur because the voter abstained or the recording device did not register a mark.
Overvoted ballots - Ballots that record a vote in more than one place for a given office (unless the ballot explicitly allows for more than one choice to be made.) May occur because the voter clearly marked more names than allowed. Often occurs when a voter places a legal mark nest to a candidate's name and then writes the same name on the 'write-in candidate' line on the ballot."
Kay J. Maxwell, President of the League of Women Voters of the United States, stated in her May 5, 2004 testimony before the United States Election Assistance Commission:
"Residual votes represent the votes that do not properly record the voter's intent, or don't record any vote at all because of problems in voting mechanisms. This is an ongoing problem that regularly means that millions of votes are lost."