The Association - XKCD version

March 6, 2009
Posted by Jay Livingston

Last week, I criticized the way the press had played up an article on rap music and sex. The article implied cause where the article had established only “association.” I speculated that the reporters hadn’t taken even a basic course in sociology or statistics. I guess they don’t read XKCD either.

Or is it really about post hoc ergo propter hoc?

Mapping Mortgages

March 6, 2009
Posted by Jay Livingston

USA Today had maps showing the rise in overpriced houses – mortgages that were more than four times the applicant’s income – 2000 to 2007.

)Click on the image for a larger view.)

At the USA Today website , you drag a slider over the map to change from one to the other – cool technically but not especially useful.

I wondered if there might be any similarity between the 2007 map and the county map of the Presidential election.

It’s hard to tell from just looking. If there is a correlation, it’s probably driven by the swath down the middle of the country – light blue for affordable mortgages, Republican red in the election – but I don’t have the original data. And remember, these are counties, not houses or voters. That large geographic area probably accounts for far fewer of each than do the areas east and west of it.

I've Got a Fast Connection So I Don't Have to Wait . . .

March 4, 2009
Posted by Jay Livingston

You don’t expect an article form the Journal of Economic Perspectives make it to the national news . . . unless it’s about pornography, politics, and piety. Here are some typical headlines.
Red Staters Buy More Online Porn than Blue Staters (USA Today)
Red State Porn Purchasing Power (SF Chronicle)
Porn in the USA: Conservatives Are Biggest Consumers (ABC News)
The study, by Benjamin Edelman at the Harvard Business School, look at paid subscriptions to online porn sites from a single company (one of the top ten), which provided Edelman the zip codes of their subscribers.

Here’s the table that got the most attention in the press.

(Click on the table to see a larger version.)

In his New York Times blog, Charles Blow reprinted the table with the third column highlighted in red. That column shows several conservative states (Utah, Araknsas, Oklahoma) in the top ten, and several liberal states (New Jersey, Oregon, Connecticut) in the bottom ten. Blow says, “New evidence suggests that people who live in states that laud morality may also be the most lascivious.”

Is that what Edelman found? Is that even what the table shows? Look again.

When Edelman used porn subscriptions per capita (column 1), New Jersey, Connecticut, and Massachusetts were in the top ten, a finding that the media pretty much ignored. When he changed the denominator to homes with Internet access (column 2), New Jersey and Massachusetts were still in the top ten, joined by California. It was only when he changed the denominator to homes with broadband that some of these liberal states wound up in the lowest fifth, and states like Oklahoma and Arkansas hit the top ten.

Here’s what really happened. When it comes to paying for online porn, variation by state is fairly small. As Edelman says at the conclusion of his article, “interest in online adult entertainment [is] relatively constant across regions.” But regions do differ in broadband access. Using broadband rather than population has a big impact. Connecticut, Oregon, Massachusetts, California, and New Jersey are all high in broadband access (near 60% of households); Oklahoma, Arkansas, and West Virginia are all in the lowest quintile (less than 40%).

What column 3 shows is not so much who’s paying for porn but who has broadband. “Avenue Q” fans will understand:

(The first 30 seconds or so is all you need to get the idea, although the best line comes near the end.

The outlier in my analysis is Utah – lots of broadband, lots of porn. Can any Mormonologists out there explain this?

Nobody Knows You When You're Downwardly Mobile

March 2, 2009
Posted by Jay Livingston

Mark Kleiman notes a line from a New York Times story about downward mobility. The line concerns Ame Arlt, age 53, who had been making $165,000 a year as vice president at a media company. Now she makes $10-15 an hour doing mostly data entry.

Saddest line in the story: “Even though she has parted ways with some friends because she is no longer in their social stratum . . . “ I’ll have to get a new dictionary. The one I have seems to have an obsolete definition of the word “friend.”

Did Mark think that her former friends had abandoned her? That was my first thought. In my mind’s ear, I heard Billie Holiday singing the bridge to God Bless the Child:

Money – you’ve got lots of friends
Waitin’ round your door
When it’s gone and spending ends
They don’t come no more.

These lines are at 1:16 into this clip.

But on reading the sentence a second time, I got the impression that Ms. Arlt was the one who had decided to let the friendships drop. It’s not about their snobbery, it’s about her sense of self.

That interpretation may be more accurate, but it’s certainly not the more popular one. In fact, as I was trying to think up a title for this post, I ran through the lyrics of all the “friend” songs I could think of, and they all said the same thing: “I’ll be your friend even when things go bad for you.” None of them looked at it from the position Ms. Alt is now in. None of them said, “When I’m down and out and you’re still in good shape, I won’t be self-conscious or ashamed about still being friends with you.”

Can anyone think of a song, or anything else, that expresses that idea?