Friday, August 26, 2011

Brains! (Updated)

I really should not be having to write this post.  And yet Rick Perry leaves me no choice (I suspect that the governor of Texas will be taking up far too much of my time should he actually receive the Republican nomination).  Time for an actual quote from Rick Perry's speech announcing his candidacy for the 2012 Republican nomination:  "We’re dismayed at the injustice that nearly half of all Americans don’t even pay any income tax."

This is a perfect example of what some bloggers have come to call a "zombie lie:" a lie or half-truth that continues to be repeated ad nauseum no matter how many times fact checkers attempt to shoot it down (like all zombies, these lies cannot be killed).

Perry is certainly not the first conservative figure to harp on this point.  Fox News, the editorial page of the Wall Street Journal, the Tax Foundation and quite a few conservative politicians have been complaining about this for a while.  The number of households that pay no income tax is dutifully trotted out, and the Randian conclusion that we're all supposed to draw from the statistic is obvious: the rich carry all the burdens in our society, while those at the lower end of the income distribution are nothing but lazy freeloaders who don't even pay anything to support the vast federal leviathan.

Monday, August 22, 2011

Statisticians in the News

From the BBC.  I do have to ask though: when did we acquire the reputation as emotionless calculating machines?  Yes, we tend be logically minded people who enjoy mathematical questions, but Mr. Spock exists only in the world of fiction.

Wednesday, August 17, 2011

Do They Have to Make it so Easy?

As some of my readers may remember, when I began blogging, I divided numeric distortions into the following three categories:
1) lies
2) damned lies
3) statistics

I expected to spend my time writing about category 3.  Yet for some reason I'm now writing about category 2.  The latest from Rush Limbaugh (emphases mine):
Obama is always running around complaining and whining and moaning about all that he inherited from George W. Bush.  Well, he inherited a AAA credit rating, an unemployment rate of 5.7%.  Does anybody doubt that this is on purpose?
Where does Limbaugh get his numbers, exactly?  Here's the seasonally adjusted unemployment rate from January 2008 through the end of 2009 (source: US Bureau of Labor Statistics via Google's Public Data Explorer):

(You can get specific numbers for each month by rolling your cursor along the trend line in the plot, and you can click on the "explore data" link to play around with this a little more).  In November of 2008, when Obama was elected, unemployment stood at 6.8%, and had been on a steady upward trajectory since April of 2008, before Obama had even won the Democratic primary.  By the time Obama took office in January of 2009, unemployment had climbed to 7.8%.  In fact, unemployment in the US hasn't been at or below 5.7% since June of 2008.  So I suppose Rush thinks Obama took over from Bush from the moment he won the Democratic primary?

Not to be outdone, Sean Hannity of Fox News claimed that unemployment stood at 5.6% when Obama took over from Bush:

Look, I am not here to defend Barack Obama's economic record.  Unemployment has failed to go under 8.8% since he took office, and I might add that the BLS's numbers probably understate the true extent of unemployment because they don't account for people who want to work full-time, but are forced into part-time jobs, or people who are working at jobs for which they're grossly overqualified (e.g. all the highly intelligent law school graduates out there right now who are employed, but not as attorneys).  As Christina Romer notes, high unemployment for more than 2 years should be considered a national emergency, and I think that the long-term social and political consequences of this recession will be devastating.  Obama clearly bears a lot of responsibility here.  But apparently Rush Limbaugh and Fox News are now trying to pretend that the economy was rosy when Bush left office, and that unemployment had not begun its relentless upward march before it was even clear that Obama would be the Democratic nominee (and I guess they'll soon try to tell us that Bear Stearns and Lehman Brothers didn't implode on Bush's watch either).  Damned lies, all of it.

When Statistics Really Do Matter

The Atlantic recently published an article claiming that homeopathic medicine is, well, triumphant.  We are also told that alternative medicine will succeed where allopathic medicine is currently failing.
And what statistics does this article cite to bolster its case?  Not a one.  Instead, we get quips dismissing the importance of randomized clinical trials, and a lot of anecdotes about instances where alternative medicine provided comfort to someone with a chronic condition.
Indeed, if there's a single critique to be made of alternative medicine, it is that none of its methods ever outperform the placebo in randomized clinical trials (the gold standard for testing medical treatments).  To make matters worse, most practitioners of alternative medicine claim that their methods can't be adequately tested by clinical trials (I guess calling something a non-falsifiable hypothesis is now a defense?), something that the article I linked to makes quite clear.  Paul Meier must be rolling over in his grave.

Sunday, August 14, 2011

RIP, Paul Meier

This obituary in the New York Times, of the great American statistician Paul Meier, is well worth reading.  One little point: the Kaplan-Meier estimator is actually not terribly complicated to compute.  This is part of what makes the formula such a great accomplishment.  Still, overall, this obituary is a great tribute to one of the more important statisticians of the last century, and a reminder that my discipline can have a truly positive impact on the world.

Tuesday, August 9, 2011

Here We Go Again

A friend recently pointed me to an article in The Economist.  In the article, we're told "In June McKinsey, a consultancy, found in a survey that 30% of firms would definitely or probably stop offering insurance after 2014, when the exchanges are in place."  We've been through this before: the McKinsey study is simply not credible, because its authors failed to follow most of the rules of good surveys.  (For a refresher on this, see here and here).  So why on earth is The Economist, which claims to offer "authoritative insight and opinion on international news, politics, business, finance, science and technology," quoting a bogus survey?  Worse, why are they quoting it after quite a few credible journalists and academics have criticized its statistical failings?  Sigh.

I haven't had time to go through the related survey by the Federation of Independent Business - which apparently found that 57% of companies would consider dropping insurance completely if some employees began moving into the insurance exchanges created by the PPACA - but its findings are intriguing enough that I intend to do so as soon as possible.

Thursday, August 4, 2011

When Statistics are Correct, but Don't/Shouldn't Matter

Since President Obama recently signed the debt-limit bill that passed Congress, this issue is sort of moot, but I would like to raise it anyway.

Nate Silver and Bruce Bartlett both point out that there is significant public support for raising taxes on wealthy Americans.  The polling data they point to are accurate (and I would say that, in general, Nate Silver's assessments of political polling are top-notch).  The question however, is: who cares?  Obviously, it's valuable for us to know where public opinion lies on a lot of issues.  From my perspective, however, forcing politicians to vote in accordance with opinion polls could undermine the effectiveness of representative government.  Moreover, I think liberals should be hesitant to use these polling data to support arguments in favor of higher tax rates; many of the reforms they hold dear might never have come about if decisions in Washington were always based on polls.  Keep in mind that when the Supreme Court struck down restrictions on interracial marriage in 1967, approximately 73% of the population disapproved of interracial marriage (compared to about 17% as of 2007).  If politicians of either party feel that raising taxes right now is a terrible idea, then they should feel free to legislate accordingly.  If the public dislikes the results, we have the same remedy that we have always had: throw the bums out when they're up for reelection.