PolitiMath at PolitiFact New Hampshire

PolitiFact New Hampshire provides us an example of PolitiMath with its Sept. 19, 2014 rating of Sen. Jeanne Shaheen's ad attacking Republican challenger Scott Brown.

The ad claims Brown ranked first in receiving donations from "Wall Street," to the tune of $5.3 million.

PolitiFact New Hampshire pegged the reasonably "Wall Street" figure lower than $5.3 million:

Brown’s total haul from these six categories was about $4.2 million, or about one-fifth lower than what the ad said.

Note that national PolitiFact's Louis Jacobson, writing for PolitiFact New Hampshire, figures the difference between the two figures with the errant figure as the baseline. That method sends the message that Shaheen's ad was off on the number by about one-fifth, or in error by about 20 percent. Calculated properly, the figure in Shaheen's ad represents an exaggeration (that is, error) of 26 percent.

Curiously, PolitiFact doesn't bother reaching a conclusion on whether it's true that Brown ranks number one in terms of Wall Street giving. Jacobson says Brown led in four of the six categories he classified as Wall Street, but kept mum about where Brown ranked with the figures added up.

That makes it difficult to judge whether the 26 percent error implied by PolitiFact New Hampshire's $4.2 million figure accounts for the "Mostly True" rating all by itself.

Capricious.

For comparison, we have a rating of President Obama where the PolitiFact team made a similar mistake, calculating the error as a percentage of the errant number. In that case, Obama gave a figure that was off by 27 percent and received a rating of "Mostly True."


Afters

After a little searching we found a "Mostly True" rating of a conservative where the speaker used the wrong figure. Conservative pundit Bill Kristol said around 40 percent of union members voted for the Republican presidential candidate in 2008. The actual number was 37 percent. Kristol was off by about 8 percent. So "Mostly True."

Washington Examiner-Politifact Is Often More Politics Than Facts

Mark Hemingway of the Washington Examiner exposes flaws in Politifact's rating of Rand Paul. The Kentuckian pointed out a disparity between private and public worker compensation-

“The average federal employee makes $120,000 a year. The average private employee makes $60,000 a year.”

Politifact rated him False. They explained that Paul might confuse his audience-

Since most people usually think about how much they, their spouses and their colleagues get paid in salary alone — not salary plus benefits — we think most people hearing this statement would assume that Paul means that the average federal employee gets paid a salary of $120,000. That’s simply not true.

Politifact offered no evidence that "most people" would think Paul was talking about salary alone. And Hemingway was quick to point this out-

"So what they’re saying is not that what Paul said was literally false, but that according to how they think people will understand what he said, it’s not true. Come again?"

Hemingway concludes that despite Politifact framing the fact-check to their own ambiguous standards, they still missed the mark-

"Politifact does make one relevant point about the average private sector worker not being an apples-to-apples comparison to the average federal worker, but that has no bearing on what Paul actually said and hardly justifies the exorbitant compensation federal workers get."

You can read the entire article here.

You can also read a companion critique at Sublime Bloviations, that points out another flaw with the Politifact piece. Three months prior to the Paul rating Politifact came to a different conclusion when they rated Mike Keown.

This represents three separate fact checks on basically the same issue with two different conclusions.