[EM] Professor Avi Rubin and American Idol election methods

[Scott Ritchie]

On Fri, 2007-03-09 at 18:45 -0500, Chris Backert wrote:
> Professor and noted electronic voting security expert Avi Rubin
> recently discussed some recent American Idol "election" events. He was
> discussing some of the technical merits of a vote-by-phone system at
> the possibility of fraud while attempting how to understand how what
> he deemed a very unlikely outcome could have occurred. 
> 
> Trying to let go of the idea that this discussion includes American
> Idol, has anyone on list ever reviewed the form of election method
> used here? As far as I understand votes are in no way limited to one
> per person. I'm not sure what election method this would fall under
> (nearly unlimited votes, single-winner, forced rounds...) 
> 
I took a class on voting systems recently, and my professor's favorite
examples to use where reality TV shows.

The American idol system is particularly interesting.  Voters cast what
are essentially approval-style ballots, however only the LOSERS matter
in any given week.  They're eliminated from the show, another contest is
held next episode, and voters vote again while largely ignoring past
performances.

This creates an interesting strategy.  The primary focus is not to "win"
in terms of being the best; rather, the best strategy is to actively
avoid coming in last place.

What this means is that a "risky" strategy, such as singing a
controversial song, is generally a bad idea on American idol.  Unless a
particular singer truly believes they're the worst among the group and
are near certain to be voted off next, making an "average, proven"
performance and finishing in the middle of the pack is a fine strategy.

Contrast this with a typical talent show with only a single round of
voting.  Here, the best hope for winning is to be recognized and visibly
ahead of everyone else.  This is especially true with plurality-style
ballots.  In such a contest, contestants should instead be risk-seeking,
hoping to get as much variance in their performance as possible.  Since
an "average" performance is a near-certain defeat, only by throwing the
dice and hoping to do exceptionally well can someone win in a
single-round talent show.

Thanks,
Scott Ritchie