Thursday, April 26, 2012

Obama in 2012?, Another Forecast Model

UPDATE:  Don't put too much faith in predictive models based on older election results, says one commentator, because of the changed nature of the party coalitions.

"Today the party coalitions are much more stable, and the battle is fought almost entirely between the 45-yard lines of the field. We have not seen anybody win less than 45 percent in terms of two-party presidential vote in twenty years, and it has only happened once in the House vote (to the GOP in 2008). This means that both sides have secured a solid base of 45 percent, and the range from cycle-to-cycle in terms of two-party vote share is now half of what it once was: the average difference in two-party vote share from 1948 through 1984 was 10.9 percent; since 1988 it has only been 5.8 percent. What’s more, between 2000 and 2008 a total of 10 states voted Republican and Democratic for president at least once, but between 1964 and 1972 forty-three states voted for both sides at least once.

(In Congress, this transition from regional to ideological parties has created the polarization that Beltway pundits regularly bemoan. Really, it is just a consequence of 'Democratic' now meaning 'liberal' and 'Republican' meaning 'conservative.' Fifty years ago, that was not necessarily true.) . . .

This is a lesson not just for the wonky backwaters of predictive modeling, but a good lesson for moving forward through this presidential cycle. If the only real swath of persuable voters amounts to maybe 10 percent of the electorate, then we need to be careful in how we look at the horse race. After all, we are talking about a group of people that have virtually no partisan or ideological attachments, pay very little attention to politics, and often create the crazy swings we see in the horse race polls during the course of the cycle. They are at the least fickle and at the worst maddening, as they regularly tell pollsters they have settled opinions when in fact they do not!"

Read The Weekly Standard, 90 Percent of the Electorate Is Probably Locked In.

"Political scientists have long known that you can predict most of what will happen in a presidential election with just a few key pieces of information: how the economy does, for instance, and the incumbent’s approval ratings in the summer. If you have those two numbers — even before you know the opponent, the campaign strategies or the issues — you can usually call the winner.

What these models suggest, in other words, is that the ephemera of elections aren’t that important. Not that this stuff doesn’t matter at all: Elections are often close, and a few percentage points can mean the difference between defeat and victory. But these micro-scandals mostly serve to distract us from the things that really do matter. And I don’t want to spend the next seven months distracted."

Read the Washington Post, 'Scandals' don’t predict election results. But this formula might., which includes a forecast model that "uses just three pieces of information that have been found to be particularly predictive: economic growth in the year of the election, as measured by the change in gross domestic product during the first three quarters; the president’s approval rating in June; and whether one of the candidates is the incumbent.

And compare the results with The New Times forecast model discussed previously.

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