In a news article entitled, “Inequality might start before we’re even born,” Carolyn Johnson reports:
Another study, forthcoming in the Journal of Human Resources, analyzed birth outcomes in counties where the home team goes to the Super Bowl. . . . The researchers found that women in their first trimester whose home team played in the Super Bowl had measurably different birth outcomes than pregnant women whose teams did not go to the championship. There was a small, 4 percent increase in the probability of having a baby with low birth weight when the team won.
Garden. Of. Forking. Paths.
The magnitude of the change was tiny, but what was striking to Mansour [one of the authors of the study] was that it was detectable at all, in studying Super Bowl history from 1969 to 2004.
On the contrary, I’m not surprised at all. Given that researchers have detected ESP, and the effects of himmicanes, and power pose, and beauty and sex ratio, etc etc etc., I’m not surprised they can detect the effect of the Super Bowl. That’s the point of researcher degrees of freedom: you can detect anything.
As a special bonus, we get the difference between significant and non-significant:
The chances of having a low birth weight baby were a bit higher when the team won in an upset, suggesting that surprise may have helped fuel the effect. There was little effect when the team lost.
Really no end to the paths in this garden.
To her credit, Johnson does express some skepticism:
There’s a huge caveat to interpreting these studies. . . . That means researchers have to use natural experiments and existing data sets to explore their hypothesis. That leads to imaginative studies — like the Super Bowl one — but also means that they can’t be certain that it’s the prenatal experiences and not some other factor that explains the result.
But not nearly enough skepticism, as far as I’m concerned. To say “they can’t be certain that . . .” is to way overstate the evidence. If someone shows a blurry photo that purports to show the Loch Ness Monster, the appropriate response is not “they can’t be certain that it’s Nessie and not some other factor that explains the result.”
Sure, you can come up with a story in which the Super Bowl adds stress that increases the risk of low birth weight. Or a story in which the Super Bowl adds positive feelings that decrease that risk. Or a story about the relevance of any other sporting event, or any other publicized event, maybe a major TV special or an election or the report of shark attacks or prisoners on the loose or whatever else is happening to you this trimester. Talk is cheap, and so is “p less than .05.”
P.S. One more thing. I just noticed that the news headline was “Inequality might start before we’re even born.” What do they mean, “might”? Of course inequality starts before we’re even born. You don’t have to be George W. Bush or Edward M. Kennedy to know that! It’s fine to be concerned about inequality; no need to try to use shaky science to back up a claim that’s evident from lots of direct observations and a huge literature on social mobility.