Short Takes: Gerrymandering, Effect Sizes, Race Times and More

I seem to have a lot of articles piling up that I have something to say about, but not enough for a full post. Here’s 4 short takes on 4 current items:

Did You Hear the One About the Hungry Judges?
The AVI sent me an article this week about a hungry judge study I’ve heard referenced multiple times in the context of willpower and food articles. Basically, the study shows that judges rule in favor of prisoners requesting parole 65% of the time at the beginning of the day and 0% of the time right before lunch. The common interpretation is that we are so driven by biological forces that we override our higher order functioning when they’re compromised. The article rounds up some of the criticisms of the paper, and makes a few of its own…namely that an effect size that large could never have gone unnoticed. It’s another good example of “this psychological effect is so subtle we needed research to tease it out, but so large that it noticeably impacts everything we do” type research, and that should always raise an eyebrow. Statistically, the difference in rulings is as profound as the difference between male and female height. The point is, everyone would know this already if it were true. So what happened here? Well,this PNAS paper covers it nicely but here’s the short version: 1) the study was done in Israel  2) This court does parole hearings by prison, 3 prisons a day with a break in between each 3) prisoners who have legal counsel go first 4) lawyers often represent multiple people, and they chose the order of their own cases 5) the original authors lumped “case deferred” and “parole denied” together as one category. So basically the cases are roughly ordered from best to worst up front, and each break starts the process over again. Kinda makes the results look a little less impressive, huh?

On Inter-Country Generalization and Street Harassment
I can’t remember who suggested it, but I saw someone recently suggest that biology or nutrition papers in PubMed or other journal listings should have to include a little icon/picture at the top that indicated what animal the study was done on. They were attempting to combat the whole “Chemical X causes cancer!” hoopla that arises when we’re overdosing mice on something. I would like to suggest we actually do the same thing with countries, maybe use their flags or something. Much like with the study above, I think tipping people off that we can’t make assumptions things are working the same way they work in the US or whatever country you hail from. I was thinking about that when I saw this article from Slate with the headline “Do Women Like Being Sexually Harassed? Men in a New Survey Say Yes“. The survey has some disturbing statistics about how often men admit to harassing or groping women on the street (31-64%) and why they do it (90% say “it’s fun”), but it’s important to note it surveyed men exclusively in the Middle East and Northern Africa. Among the 4 countries, results and attitudes varied quite a bit, making it pretty certain that there’s a lot of cultural variability at play here. While I thought the neutral headline was a little misleading on this point, the author gets some points for illustrating the story with signs (in Arabic) from a street harassment protest in Cairo. I only hope other stories reporting surveys from other countries do the same.

Gerrymandering Update: Independent Commissions May Not be That Great (or Computer Models Need More Validating)
In  my last post about gerrymandering, I mentioned that some computer models showed that independent commissions did a much better job of redrawing districts than state legislatures did. Yet another computer model is disputing this idea, showing that they aren’t. To be honest I didn’t read the working paper here and I’m a little unclear over what they compared to what, but it may lend credibility to the Assistant Village Idiot’s comment that those drawing district maps may be grouping together similar types of people rather than focusing on political party. That’s the sort of thing that humans of all sorts would do naturally and computers would call biased. Clearly we need a few more checks here.

Runner Update: They’re still slow and my treadmill is wrong
As an update to my marathon times post, I recently got sent this websites report that  showed that US runners for all distances are getting slower. They sliced and diced the data a bit and found some interesting patterns: men are slowing down more than women and slower runners are getting even slower. However, even the fastest runners have slowed down about 10% in the last two decades. They pose a few possible reasons: increased obesity in the general population, elite runners avoiding races due to the large numbers of slower runners, or in general leaving to do ultras/trail races/other activities. On a only tangentially related  plus side, I thought I was seriously slowing down in my running until I discovered that my treadmill was incorrectly calibrated to the tune of over 2 min/mile.  Yay for data errors in the right direction.

 

 

International data – beware the self reporting

Maybe it’s just because the Olympics are on, but I’ve run in to a few interesting international statistics lately that gave me pause.

The first was regarding infant mortality.  After Aaron Sorkin’s new show The Newsroom incorrectly reported that the US was 178th in infant mortality (really, you think there are 177 countries you’d rather give birth in?), I went looking for the infant mortality listings across the world.  The US does not typically do very well in terms of other industrialized countries.  
There are a few interesting reasons for that….we have a much larger population than most of the countries that beat us, and it’s spread out over a much larger area.  Our care across areas/populations tends to be more uneven, states vary wildly on issues like access, health insurance, prenatal care, etc. Our records however, tend to be meticulous….there is very little doubt that we capture nearly all infant mortality that actually occurs.  This combination can put the US at a huge disadvantage in these statistics (10-30% according to the best published studies).
This raises the point of why Cuba tends to beat us.  Now, realistically speaking, if you or someone you love had to give birth, would you seriously pick Cuba over the US?  Would anybody?  And yet they look safer given the data….which is all self reported.  I have no problems believing that Singapore outranks us, but I’m skeptical of any country that might have an agenda.  Worldwide, there is actually very little consensus on what is a “live birth”, and the US tends to use the “any sign of life” definition.  
On the other end of the spectrum, I saw this piece recently on gun control.  I’ve covered misleading gun stats before (suicides are often combined with homicides to get “death by gun violence” numbers).  One of the interesting facts the article above points out is that internationally, gun deaths are only counted when it’s civilian on civilian violence.  This is certainly fine in the US…I would think we wouldn’t want to count every time the police had to open fire, but in countries with, um, more questionable police tactics, this could cause some skewing (Syria was cited as one such example).  
Data is hard enough to pin down when you know the sources have no vested interest in misleading you….international rankings will never be free from such bias.