Saturday, October 03, 2015

The "Spillover Effects" of Having to Pee: You Lie Better?

Seriously.  They actually say "spillover effects."  Me gusta.

The inhibitory spillover effect: Controlling the bladder makes better liars 

Elise Fenn et al.
Consciousness and Cognition, December 2015, Pages 112–122

Abstract: The Inhibitory-Spillover-Effect (ISE) on a deception task was investigated. The ISE occurs when performance in one self-control task facilitates performance in another (simultaneously conducted) self-control task. Deceiving requires increased access to inhibitory control. We hypothesized that inducing liars to control urination urgency (physical inhibition) would facilitate control during deceptive interviews (cognitive inhibition). Participants drank small (low-control) or large (high-control) amounts of water. Next, they lied or told the truth to an interviewer. Third-party observers assessed the presence of behavioral cues and made true/lie judgments. In the high-control, but not the low-control condition, liars displayed significantly fewer behavioral cues to deception, more behavioral cues signaling truth, and provided longer and more complex accounts than truth-tellers. Accuracy detecting liars in the high-control condition was significantly impaired; observers revealed bias toward perceiving liars as truth-tellers. The ISE can operate in complex behaviors. Acts of deception can be facilitated by covert manipulations of self-control.

Nod to Kevin Lewis

Friday, October 02, 2015

A Taste of Headline Heaven

My love of an excellent, self-contained headline is well-documented.  One advantage of this is that sharp-eyed KPC readers send in examples.

This one...oh, man, this one is excellent:

"Watch woman yell 'bear don’t eat my kayak' as bear eats kayak"

It's all there:  pathos, drama, action.  Lovely.

Thanks to Rob Hallford, who offered this analysis:  "My favorite part is when she screams that the kayak "doesn't even taste good." Like a) she's tried it and b) knows what tastes good to bears. In fact, seasoned with her tears, I bet it tasted pretty damn good. "

Keep 'em coming, folks. 

Update:  Loyal reader DD notes that the Gawker headline is also well done:  "Bear Politely Ignores Woman Yelling at Him to Stop Eating Kayak."

Thursday, October 01, 2015

Last meals

Oh Oklahoma. you just can't do anything right.

Take the case of this dude Richard Glossip, on death row for murder for hire.

He's already had two last minute stays of execution, this time because the state did not get the correct third drug for its 3 drug lethal injection cocktail.

No matter what you think of the case or of capital punishment, can you imagine being set to be executed twice already and getting last day reprieves and knowing that it will happen again in 37 days?

Jeebus help us all for what happens in our penal system.

Here, by the way, is the menu for Glossip's second last meal:

On Tuesday evening, Glossip received a second last meal: a medium double-bacon, double-cheese pizza from Pizza Hut; two orders of fish and chips from Long John Silver's; and a Baconater and strawberry malt from Wendy's.

I wonder what he'll ask for on his 3rd one. I wonder how many last meals this poor bastard will have.

By the way, here's my last meal request if it ever comes down to it:

Wagyu beef skirt steak(medium rare), mexican-style corn on the cob, risotto, charred brussels sprouts, key lime pie.

I'd like the pie to come from The Tea House in Santa Fe, the steak, risotto and brussels sprouts from Red Prime in OKC and the corn from Passion Latin Fusion in Albequerque.

Wednesday, September 30, 2015


Okay, so people make fun of the bad forecasts of economists.  Fair enough.  But economists are trying to forecast actions of sentient, prospectively focused creatures.

Hurricanes are just big unruly piles of wind.  But we can't forecast THOSE either.  Check out this "ensemble" forecast for the next week (click for an even more incoherent image):
Of course, if we can't predict the actions of "big unruly piles of wind" I guess forecasts about Congressional votes are also off the table. 

Tuesday, September 29, 2015


How Disgust Influences Health Purity Attitudes 

Scott Clifford & Dane Wendell 
Political Behavior, forthcoming 

 Abstract: Food and health regulations are increasingly being pushed onto the political agenda, with rising concerns about genetically modified foods, obesity rates, and vaccination. Public beliefs and attitudes on these issues often conflict with the scientific evidence, yet we know relatively little about what influences opinion on these issues. The public lacks clear partisan cues, and many food and health attitudes cut across the ideological spectrum. We argue that these issues represent new 'purity' attitudes that are driven by the emotion of disgust. Across three studies, both by measuring individuals' trait disgust sensitivity and experimentally inducing an emotional state of disgust, we demonstrate the impact of disgust on food and health policy attitudes. Our results show that greater sensitivity to disgust is associated with support for organic foods, opposition to genetically modified foods, and anti-vaccination beliefs. However, we find only limited evidence that experimentally manipulated disgust affects attitudes toward genetically modified and organic foods. Overall, our results demonstrate that disgust plays an important role in attitudes regarding public health and broadens our understanding of purity attitudes.

Thanks to Kevin Lewis

Monday, September 28, 2015

Friends don't let Friends do IV

Just don't do it. And if you must do it, dear God please don't do it with a Arellano-Bond type dynamic panel model (it's the worst, Jerry).

Here are the problems.

First of all, no matter what you may have read or been taught, identification is always and everywhere an ASSUMPTION. You cannot prove your IV is valid.

Second, no matter what you may have read or been taught, the family of Sargan-type tests are tests of OVER-IDENTIFICATION, not identification. You can "pass" the test and still not achieve valid identification.

Third, passing the tests, useless though they are, in any realistic fashion does not mean failing to reject the null at the .05 or even the .10 level.


The reason why is that our worry is we might fail to reject a false null. This is type II error. Choosing .05 essentially MAXIMIZES the chances of committing a type II error (minimizes the power of the test). I'd like to see p-values on the order of at least .25 to .30 (or higher).

Since identification is done by assumption, theory becomes super-important. The right way to do this in my view is by recognizing that the equation you seek to estimate is part of a system and the properties of that system will let you know whether identification is achievable or not.

If not, too bad. Estimate a reduced form and be happy.

I pretty much refuse to let my grad students go on the market with an IV in the job market paper. No way, no how. Even the 80 year old deadwoods in the back of the seminar room at your job talk know how to argue about the validity of your instruments. It's one of the easiest ways to lose control of your seminar.

We've had really good luck placing students who used Diff in diff (in diff), propensity score matching, synthetic control, and even regression discontinuity. All of these approaches have their own problems, but they are like little grains of sand compared to the boulder-sized issues in IV.