“I Cannot Tell a Lie”

November 9, 2012
Posted by Jay Livingston

The father of our country may have been scrupulously truthful, but at least one of his namesakes has been fudging the data.

From Inside Higher Ed

George Washington University on Thursday became the third private university this year to admit that it has been reporting incorrect information about its new students -- both on the university's website and in information provided to U.S. News & World Report for rankings.

In the case of GW, the university -- for at least a decade -- has been submitting incorrect data on the class rank of new students. For the most recent class of new students, George Washington reported that 78 percent of new students were in the top 10 percent of their high school classes. The actual proportion of such students is 58 percent.

The irony goes beyond the name.  Universities all have rules about plagiarism and cheating on exams, and in the Student Handbook, accompanying the penalties and procedures section, schools sometimes add a righteous explanation: going out in the world disguised with a phony GPA is not only morally wrong, it is ultimately self-defeating. 

As if.

Cheating is rational, and the conditions that make it rational are the same ones that make it rational for George Washington to tell a lie. To judge the quality of a student or school in some meaningful way would be just too cumbersome.  You would have to get to know the person or school in some deeper way.  But when you have many students to grade and many schools to rate, it’s just so much more convenient to reduce all that information to a couple of numbers.  And it’s much easier to manipulate the numbers than it is to change what those numbers supposedly represent.

Predictions and Results

November 7, 2012
Posted by Jay Livingston

“Well, Howard, my predictin’ days is over,” said Muhammed Ali, even though the champ had been fairly accurate at predicting how many rounds an opponent would last. 

My post yesterday quoted Peggy Noonan predicting a Romney win.  On Fox last night, when one of the anchors asked Noonan if she were “surprised” by the results, she dodged the question and said only that she was disappointed.  Are her predicting days over?  Unlikely.

I contrasted Noonan’s “all the vibrations are right” methodology with Nate Silver’s thorough and complicated Bayesian model.  Conservatives accused Silver of liberal bias (and effeminacy), and they offered their own unbiased, clear-eyed  predictions. 

How did the prognosticators do?  Well, if somebody had bet on the Bayes, they would have cleaned up.  Here’s a scorecard.  I filled in some of the blanks in the grid that Neil Sihnababu posted at VoteSeeing .  Right now, the electoral vote stands at 303-206, with Florida not yet called, though most experts have put it in the Obama column.  Assuming that Florida is blue, Silver’s electoral prediction is perfect.  As for the battleground states, they all went for Obama (again, assuming Florida).  So did Nevada, adding one extra wrong prediction to Steve Forbes’s clear-eyed predictions.

(Click on the table for a larger view.)

You’d think that Karl Rove, George Will, and the others who did about as well as P’lod would follow Ali’s example.  Or at least, they would adjust their models, if they had any.  Or they would stop scoffing at science when it doesn’t tell them what they want to hear.  But don’t bet on it.

UPDATE:  Gabriel Rossman dresses up in his St. Paul costume (left over from Halloween, presumably) to deliver the same message. [Note for non-stats people who click on the link to Gabriel’s blog:  CLT = Central Limit Theorem.]

One More Prediction

November 6, 2012
Posted by Jay Livingston

In the previous post, I foolishly looked only at representatives from the New York Times (Nate Silver) and The Wall Street Journal (Peggy Noonan).  I overlooked a third important publication, The Weekly World News.*

The full story is here. 

But seriously folks, Neil Sihnababu at VoteSeeing, besides providing the link to unerring P’lod, has a nice table for scoring the predictionistas on the swing states as well as on the overall vote.

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*  For an earlier post on the WWW and similar tabloids, go here.

Prediction Methodology - Not Too Swift

November 6, 2012
Posted by Jay Livingston

One of the first things I try to get students to understand is the difference between systematic evidence and anecdotal and impressionistic evidence.  Or no evidence, which usually takes the form of “We don’t need studies to know that . . . .” or “Common sense tells us . . . .”

So in one corner we have Nate Silver (known in some circles as Nate the Great at Five Three Eight), systematically weighing the data from polls and other sources.  He sees Obama as the likely winner.

And then there’s Peggy Noonan at The Wall Street Journal.

Is it possible this whole thing is playing out before our eyes and we’re not really noticing because we’re too busy looking at data on paper instead of what’s in front of us?

In front of her eyes is victory for Romney.  Here are some more excerpts that show the evidence she uses as the basis for her prediction.

Among the wisest words spoken this cycle were by John Dickerson of CBS News and Slate, who said, in a conversation the night before the last presidential debate, that he thought maybe the American people were quietly cooking something up, something we don’t know about.

I think they are and I think it’s this: a Romney win.

There is no denying the Republicans have the passion now, the enthusiasm.
it feels like a lot of Republicans have gone from anti-Obama to pro-Romney.
And there is Obama, out there seeming tired and wan, showing up through sheer self discipline.

All the vibrations are right. A person who is helping him who is not a longtime Romneyite told me, yesterday: “I joined because I was anti Obama—I’m a patriot, I’ll join up But now I am pro-Romney.”

And there’s the thing about the yard signs. In Florida a few weeks ago I saw Romney signs, not Obama ones. From Ohio I hear the same. From tony Northwest Washington, D.C., I hear the same.

I imagine going to the World Series.  The guy at the hot dog stand says he thinks the Tigers are about to make a move.  I see Detroit players’ faces, full of passion and enthusiasm; the Giants look tired and wan. The Tigers are getting hits.  They even had a home run.  Their pitchers are tall and strong.  And then there’s the thing about caps – all those Detroit caps with the old English D.  I see them everywhere.

It all points to a big win by the Tigers. Clearly, the Giants are toast.

And then some nerd – “a man of very small stature, a thin and effeminate man with a soft-sounding voice, a poster child for the New Castrati”* – taps me on the arm and points to the scoreboard which posts the number of runs that each team has actually scored and the number of games that they have won.

Yes, Romney could win.  But remember Damon Runyon’s riff on Ecclesiastes: “The race is not always to the swift, nor the battle to the strong, but that's how the smart money bets.”

And they’re betting Obama.  At In-trade, a $100 bet would bring Ms. Noonan $300, and somewhat more if she bet in the UK.  My own hunch is that betting a bundle on Romney right now is not too swift.

UPDATE:  Another Republican speechwriter-turned-columnist, Michael Gerson, is yapping at Nate Silver.  John Sides at The Monkey Cage offers an excellent critique of Gerson and a defense of data- based social science.  (It is kind of depressing – Gerson and Noonan and the rest are intelligent people, and yet they force you to defend the radical idea of using systematic evidence.  But then again, their party is the standard-bearer for people who think that global warming is a myth and that earth is only 7000 years old.)

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 * Yes, this is what someone at the right-wing examiner.com actually wrote about Nate Silver.  I am not making this up.