Tuesday, October 30, 2012

Survey Says ...

After discussing politics with a friend this morning, I was inspired to make the rounds of sites that accumulate political polling results and see what they all are saying. All results accessed on the web late afternoon on November 6th.

Real Clear Politics
Obama 201 +/-61
Romney 191 -/+61
Toss Ups 146
Obama by +10 ECV
(edit: those error bound probably belong to the 538 analysis, not RCP).

Intrade Presidential Election 2012
Obama 64.6% win
Romney 35.4% win

FiveThirthyEight 
Obama 294.6 ECV
Romney 243.3 ECV
~72.9% Obama wins

Obama 265
Romney 206
(Comment: therefore 67 are not certain)

Election Analytics 
Obama 291.4
Romney 246.6
~95% Obama wins

I have arranged these in increasing order of favor for Obama winning the 2012 election. Real Clear Politics and Talking Points Memo are sites I do not regularly follow, so I have no clear opinion of their methods. I suspect these sites have a conservative and liberal biases (respectively) but I have not direct evidence for that. Certainly if they are both presenting statistical results in an unbiased manner, they ought to have about the same conclusion. All I can really say here is that RCP doesn't offer much of a direct election forecast.

Edit: Intrade is another site I don't follow, but it has been getting a lot of media attention too.

I personally favor the methods Nate Silver uses on FiveThirtyEight, as I consider it to be the most technically sophisticated analysis, and it takes economic data into account as well. Silver offers a lot of day-to-day commentary on daily polling and his predictive model. Since the Democrats have lead the elections since the blog started in 2008, many of those prediction have been that Democrats are going to win. Some people interpret this an a liberal bias, but Silver's Senate predictions have been very good, and it not a bias if he is correct.  I have never seen Silver make anything close to an endorsement, and so on that basis I think FiveThirtyEight gives the most unbiased political analysis available.

Election Analytics is different from the others. It's a small academic page rather than a news site. Their statistical methods are sound, but they make some strong assumptions, which seems to be why they are able to make such a strong prediction for Obama winning. I haven't looked into just what these assumptions are, so I can't say if they are justified or not.

All this might not make my friend happy, but all the data is saying pretty much the same thing, with varying degrees on certainty.

Update: Added Intrade prediction at the suggestion of +Kevin Clift. Accessed the morning of 10/31/12.
Edit: next time I'll include this site too: http://electoral-vote.com/