Prediction Markets Update (September 14, 2008)

Tonight, (at 8:10 p.m. Central time), the McCain Intrade contract (2008.PRES.McCAIN) is trading at 52.5, whereas the Obama Intrade contract (2008.PRES.OBAMA) is trading at 47.1; 2008.PRES.McCAIN is 1 point higher than it was the last time I posted a blog entry about the election (on Saturday, September 12), whereas 2008.PRES.OBAMA is .9 points lower.

Examining the state-by-state contracts, I find that by using a cutoff price point of 55 for allocating Electoral College votes, that this continues to “give” Barack Obama 264 Electoral College votes and John McCain 265 Electoral College votes. However, I couldn’t help but notice that many of the bid-ask-last price quotes and volume statistics for the various state-by-state contracts haven’t budged since Friday, so apparently there hasn’t been much investor interest in these contracts this weekend!

Turning our attention next to Nate Silver’s PECOTA model (see FiveThirtyEight), Mr. Silver’s model now has McCain winning the Electoral vote by a margin of 289 to 249.