US Presidential Election 2012

Statisticians Nate Silver and Sam Wang run circles around the pundits

The remarkably accurate predictions of election results by statisticians Nate Silver and Sam Wang has given new credence to number crunching

PUBLISHED : Friday, 09 November, 2012, 12:00am
UPDATED : Friday, 09 November, 2012, 12:03pm

Tuesday's election result was not just a victory for President Barack Obama, but a validation for the new breed of so-called "big data" number crunchers.

They include New York Times blogger Nate Silver, whose uncanny accuracy in predicting the result has turned him into something of a mathematical rock star.

Silver used his FiveThirty Eight blog to chart the likelihood of victory for Obama or Mitt Romney. His algorithms consistently and clearly pointed to an Obama win - in defiance of conventional wisdom that the race was too close to call - turning him into a hate figure of right-wing pundits, who derided his mathematical "voodoo" as biased.

He was even criticised by one conservative writer for being "thin and effeminate".

Undeterred, on election day he offered a 90.9 per cent probability of an Obama win, predicting 332 as his most likely electoral college tally.

While critics might sneer at correctly predicting a presidential race's outcome, something a coin toss could achieve half the time as Silver himself points out, they have a harder time arguing against the fine print. Silver's model correctly predicted the likeliest presidential outcome in 49 states; it will be correct in all 50 if Obama's lead holds in Florida. That's 332 electoral college votes.

The odds of doing that on a coin toss is less than a one in a thousand trillion. Or, precisely one in 1,125,899,906,842,623.

"Here is the absolute, undoubted winner of this election: Nate Silver and big data," said Chris Taylor in an opinion column on the website Mashable.

"What does this victory mean? That mathematical models can no longer be derided by "gut-feeling" pundits. That Silver's contention - TV pundits are generally no more accurate than a coin toss - must now be given wider credence."

It was a similar result for three other models, including from Princeton University neuroscientist Sam Wang, Stanford's Simon Jackman and Emory University's Drew Linzer.

The results evoked the popular book and film starring Brad Pitt Moneyball, which showed how statistical models can help win in baseball.

Obama's victory "is also a victory for the Moneyball approach to politics," said John Sides, a political scientist at George Washington University.

"It shows us that we can use systematic data - economic data, polling data - to separate momentum from no-mentum, to dispense with the gaseous emanations of pundits' 'guts,' and ultimately to forecast the winner," he said in a blog post.

In the weeks leading up to the election, Silver - whose blog Five- ThirtyEight is named after the number of electoral college votes up for grabs - and others had been pilloried by conservative commentators.

Dean Chambers on Monday predicted a narrow Romney win in electoral votes. Conservative consultant Dick Morris had argued that the polls "understate" the number of people who favoured Romney, and ahead of the election predicted a "landslide" for the Republican.

On Wednesday, Morris acknowledged he was wrong: "I've got egg on my face," he said.

Princeton's Wang, who said he would "eat a bug" if Romney won Ohio, also accurately predicted 49 states and called Florida "a tossup." He had on Tuesday given a 99.2 percent probability of Obama's re-election.