Poblano Model Applied to MI: What Would have Happened (if Obama's name was on the ballot)

[mod mom]

Friday, May 23, 2008

Michigan: What would have happened?

I have received a couple dozen requests in my inbox asking me to apply my projection model to the state of Michigan. How would the vote have turned out if Barack Obama's name was on the ballot? Would Michigan have behaved more like Wisconsin, which Obama won handily? More like Ohio, which gave a big victory to Clinton? Or more like Indiana -- a toss-up from start to finish?

I am not going to use my regression model to answer this question; I worry that such a thing would look like a big soup of numbers, seemingly having come out of nowhere. But I am going to address the question through another approach. Specifically, I am going to take each of Michigan's 15 congressional districts, contemplate their key demographics, and identify comparable congressional districts in other states where Barack Obama's name did appear on the ballot. If we could show, for example, that Michigan's 12th district is similar to Pennsylvania's 14th, and Obama received 52 percent of the vote in PA-14, that gives us a reasonable estimate of how he might have performed there in a normal primary.

The method I use to identify similar congressional districts is called a nearest neighbor analysis, which has applications in genetics and a number of other fields. Essentially, we are trying to find out how close two points are to one another in n-dimensional space. In this case, the points represent congressional districts, and the dimensions represent different demographic variables that we have found to have a relationship with the percentage of the vote that each Democratic candidate receives. Specifically, the variables we look at are as follows:
1. African-American population share;
2. White Anglo-Saxon population share (see discussion here);
3. Share of population with bachelor's degree or higher;
4. Partisan Voting Index;
5. Percentage of population that identifies their ancestry as 'American' (see discussion here)
6. Percentage of same-sex partner households (see discussion here);
7. Hispanic population share;
8. Rural population share;
9. Percentage of voting age population age 65+;
10. Median household income;
11. Percentage of voting age population aged 18-29.

-snip

Overall, we project that Obama would have carried Michigan by a narrow margin -- about 4.0 percentage points or 80,000 votes. After accounting for delegates awarded at the statewide level, we project him to win 65 Michigan delegates to Clinton's 63. Certainly, there is some margin for error in these calculations, and Clinton could certainly have won the state herself. But it would undoubtedly have been very close. Interestingly, if you take the average of the winning margins in Indiana (Clinton by 1.2 points), Ohio (Clinton by 8.7) and Wisconsin (Obama by 17.3), you come up with an average of Obama by 2.5 points, which is very close to our estimate.


http://www.fivethirtyeight.com/2008/05/michigan-what-would-have-happened.html

[mac2]

1. Propaganda.

[mod mom]

2. "the remarkable success of the non-poll statistical model created by Poblano" by Mark Blumenthal

May 08, 2008
POBLANO'S MODEL
My latest NationalJournal.com column, about the remarkable success of the non-poll statistical model created by Poblano of FiveThirtyEight.com, is now online.
-- Mark Blumenthal

[pampango]

3. I couldn't analyze the info at the link in the OP in the 3 minutes it took you.

Kudos to having such a sharp mind. ;)