Wednesday, June 26, 2013

Strategic voting and Oxford-style debates

In determining which side wins a debate, one variant of  Oxford-style debates has people vote about a proposition before and after hearing the debate. The side that sways the most voters towards theirs wins. For example, if an audience votes initially that they are (60% For, 20% Against, 20% Undecided) and afterward they are (65% For, 30% Against, 5% Undecided) then the Against side wins (they change 10% toward their side while the other only swayed 5%). This system, though, incentivizes dishonesty in the first round. If I believe I am unlikely to change my mind during the debate, I should vote opposite my current view in the initial vote.

To see if strategic voting is a problem, one could take a debate's audience and have half of the people's votes be noted but not counted towards the winner. If the counts of the two groups differ, then something might be going on.

The harder question is how do you incentivize truth telling for those that switch.
Edit: One way maybe would be to just have a vote at the end but have a prediction market (for the final vote) be going throughout the debate. The winner of the debate is the one that moved the market price the most.