Simple New Voting Protocols provide Ballot Secrecy AND Fraud Resistance
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Conventional wisdom says elections with "secret ballots" are
protected against vote-buying and coercion, while elections
publicizing the list of all voters with their votes are immune to fraud --
but you can't have it both ways.
In a paper at EVT 07 (Boston, 6 August 2007)
mathematicians Ronald L. Rivest and Warren D. Smith refute that
conventional wisdom, potentially enabling a new level of voting integrity.
"You can have your cake and eat it too with some very
simple new voting protocols," said Professor Daniel Sleator of
Carnegie-Mellon's computer science department.
"These are explainable to children. It's surprising this
wasn't thought of 50 years ago."
Previous attempts to create such protocols have "succeeded"
in mathematical senses, but only by employing very complicated
cryptographic algorithms, challenging even for math PhDs.
Humans can't vote in those systems without computer aid, which
means that each voter would have to own a small computer
"helper" they trusted to be running correct, unhacked, voting software.
Rivest & Smith's new protocols, called "VAV," "Twin," and "ThreeBallot,"
don't require computers or cryptography, and need only low-tech mechanical
voting devices. In each, voters get take-home "receipts" they can use later
to check their vote was correctly counted -- or prove fraud -- but which
nevertheless bear absolutely no relation to that voter's vote, hence aren't
helpful for vote-selling.
How can that be? Your take-home receipt in Twin is a copy of a random
other person's vote. In VAV, each voter casts two votes and one matching
"antivote" and gets a copy of one of these three (she chooses which) as her
receipt. Either way, the receipt has no logical relation to that voter's vote.
All three Rivest-Smith protocols allow "mixing in" old-style unsafe ballots
with the new safe ones. That not only permits happy coexistence with voters
who don't want to use the new system, but also "contagiously protects" even
the unsafe ballots against fraud.
"I really love this 'easy upgrade' feature," said Doug Jones, former chair of
Iowa voting systems examiners and computer science professor at University
of Iowa.
The Rivest-Smith protocols work with a wide variety of vote-totaling systems,
not just the "plurality" system most familiar in the USA.
"Plurality is a very poor voting system," said Guy Ottewell, an astronomer
and author regarded as the inventor of Approval Voting in 1968.
"We've known better ones for 200 years."
"In plurality voting, it's 'name one candidate then shut up'," said Ottewell.
"With Approval, you name all the candidates you 'approve.' It's actually
simpler because there is no special rule outlawing 'overvoting,' and it
both delivers more information in each vote and allows voters to approve their
true favorite without being strategically foolish, so it's also more
honest information."
But why would voters want dishonestly to vote for someone other
than their true favorite?
"Two words," said Ottewell. "Ralph Nader."
"With approval voting, Nader voters aren't a problem, they're beneficial."
But Ottewell and Smith now instead advocate "Range voting,"
essentially the system used in the Olympics:
as their vote, voters score all the candidates they want to within some
fixed score-range (say 0 to 9); highest average wins.
(Range becomes the same as Approval if the range is 0 and 1.)
"Honeybees have been using range voting for millions of years, and my computer
simulations indicate it outperforms every other common vote-totaling proposal,"
said Smith.
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MORE INFO:
Fuller Story (including how VAV & Twin actually work):
/RivSmiPRshort.html
Rivest-Smith actual paper: /WarrenSmithPages/homepage/tb8.pdf
also in html: /RivSmiTB.html
Addenda to the paper: /RivSmiTBadd.html
Follow-up stories: /RivSmiPRfollow.html
EVT 07 Conference: http://www.usenix.org/events/evt07/cfp/
Rivest's lecture slides(ppt) /RivSmi3BVTevt07.ppt
Center for Range Voting: CONTACTS:
*All subjects:
Dr. Warren D. Smith 631-675-6128 warren.wds AT gmail.com (prefer email)
/WarrenSmithPages/homepage/works.html
*Approval & Range voting (AV & RV):
Guy Ottewell +1297-442247 guy AT universalworkshop.com
http://www.universalworkshop.com
*(AV, RV, and also most other vote-totalling systems too)
Prof. Steven Brams, NYU politics dept. 212-998-8510 steven.brams AT nyu.edu
(co-author of book "Approval Voting") FAX: 212-995-4184
*Computer Science:
Prof. Daniel Sleator, CMU CS dept. Office ph 412-268-7563, fax: 412-268-5576,
home ph: 412-HACKERS
RELEASE INFO:
Theoretically at any time, but someone might want first to actually hear Rivest's lecture
at about 6PM, Sheraton Boston (39 Dalton Street, 617-236-2000), 6 August 2007.
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