Electronic voting (also known as e-voting) is a term encompassing several different types of voting, embracing both electronic means of casting a vote and electronic means of counting votes. Electronic voting technology can speed the counting of ballots and can provide improved accessibility for disabled voters. However, there has been contention, especially in the United States, that electronic voting, especially DRE voting, could facilitate electoral fraud.

• Election: The votes of all of the voters to determine a winner based on the rules of a voting system
• Candidate: A choice option for the voter
• Voter: A person choosing from among the candidates
• Winner: The overall choice of candidate determined by the voting system based on the preferences of the voters
• Ballot The choices of a voter in an election

• Simple Majority
  • Each voter gets one vote
  • The winner is the candidate with more than 50% of the votes
• Plurality
  • Each voter gets one vote
  • The winner is the candidate with most votes (even if not >50%)
• Runoff
  • Eliminate all but top two vote getters.
  • “Re-vote” based on preferences.
• Instant Runoff
  • Eliminate the lowest vote getter.
  • “Re-vote” losing voters choices based on preferences. Continue until there is a winner.
• Borda Count
  • For each voter assign 1 point to the first place candidate; 2 points to the second place candidate; and so on…
  • Candidate with lowest score wins

All methods seem “fair”. The plurality winner is preferred by more people than anyone else. The runoff winner is one of the top two preferred candidates and more preferred than the other when voters are asked to choose between them The instant runoff winner is based on eliminating candidates one by one based on their preferences The Borda count winner is based on the ranking of all candidates by all voters However, someone can intentionally use one of those method to manipulate the result as he/she wish.

• Absolute result criteria
  • Majority criterion: If one candidate is preferred by a majority of the voters, then that candidate must win. (Borda Count fails)
  • Mutual majority criterion: If there is some subset of candidates such that the majority of voters prefer every candidate of the subset to every candidate outside the subset, then the winner must be in the subset. (Borda Count, Plurality fails)
  • Condorcet criterion: Chooses the Condorcet winner if one exists. (Borda Count, Plurality, Instant Runoff fails, Majority vote satisfies)
    • Condorcet winner: The candidate who, when compared with every other candidate, is preferred by more voters.
• Relative result criteria as nominees change
  • Monotonicity criterion: A candidate should not be harmed if it is given higher preference by some voters. In other words, if I change my ballot to rank winner x higher, x should not then lose the election. (Runoff, Instant Runoff fails, Plurality, Borda Count satisfies)
  • Participation criterion: The addition of a ballot where candidate A is strictly preferred to candidate B should not change the winner from candidate A to candidate B. (Instant Runoff, Any Condorcet method fails, Plurality, Borda Count satisfies)
  • Independence of irrelevant alternatives criterion: The addition of a candidate Y to an election where candidate X wins should not cause some third candidate Z to win. (Plurality fails)
• Administration criteria
  • Can we find a winner in polynomial time?
  • Can we detect cheating (sum of tallies at polling stations) in polynomial time?
• Voter criteria
  • Ease of voting
    • Too many candidates
    • Alphabetical ordering of candidates
  • Understanding of tabulation method
  • Can we rank candidates equally?

No. Can’t have a voting system that uses voters’ ranked preferences of candidates into a group winner while meeting three “fairness” criteria:

1. If every voter prefers X over Y, then the group prefers X over Y
2. If every voter’s preference between X and Y remains unchanged, then the group’s preference between X and Y also remains unchanged (even if other pairwise preferences change)
3. No single voter can always determine the group’s preference.

http://www.computerworld.com/s/article/9225816

E-voting system awards election to wrong candidates in Florida village Analysts warn that same Dominion Sequoia machines are used in nearly 300 U.S. municipalities Dominion Voting Inc.'s Sequoia Voting Systems device mistakenly awarded two Wellington Village Council seats to candidates who were found in a post-election audit to have lost their races. The results were officially changed last weekend after a court-sanctioned public hand count of the votes.

http://www.npr.org/blogs/itsallpolitics/2012/03/29/149634764/online-voting-premature-warns-government-cybersecurity-expert

Warnings about the dangers of Internet voting have been growing as the 2012 election nears, and an especially noteworthy one came Thursday from a top cybersecurity official at the U.S. Department of Homeland Security.

http://j.mp/AAsz8U

Political campaigns, which have borrowed tricks from Madison Avenue for decades, are now fully engaged on the latest technological frontier in advertising: aiming specific ads at potential supporters based on where they live, the Web sites they visit and their voting records.

1. What if voters who do not vote honestly (i.e., for candidates other than their preference, strategic voting)
2. If someone make a mistake or change their mind, can they correct my ballot?
3. How will a voting system prevent people from voting more than once?
4. What would happen if there is a power failure on Election Day?