Tag Archives: reason

Girl Power Economics

The Libertarian Blog over at Reason.com had a delightful piece today on the correlation between girl band popularity and economic growth. I’m actually not sure if it is satire or not.

“Why didn’t the United States see [strong] growth during the ’60s boom? America… lost interest in [girl bands] in favor of a self-styled “invasion” of boy groups… We went off the girl standard before France did… The Go-Go’s fueled the recovery from the early 1980s recession… The effect was strongest in the 1990s… NAFTA allowed the free exchange of angry Canuck songstress Alanis Morissette. Britain maintained low inflation and low unemployment… thanks both to economic liberalization and to the rise of the Spice Girls.

Just as the decrease in piracy is correlated with the increase in global temperatures, the economic tide seems to be correlated with girl bands. Thus, we need more pirates and more girl bands, then we will have economic prosperity and stable temperatures. As satire, this is good stuff. If gender balance in music is as good a predictor as anything else, it calls into question the validity of “real” economic predictors.

But, as I said above, I’m not sure if this is satire or not.


Risk, statistics and ethics: the AIDS Vaccine

This idea of risk that we have been discussing on TBU for a while now has come up again. The results of a new HIV/AIDS vaccine study were released this week. The Thai trial has shown some promise. The incidence of HIV was 30% lower in the group vaccinated with RV 144 than the control group.

First: the basic bioethics question. Was it OK to give a lot of people a placebo which might let them think they were protected from HIV when they were not at all protected? (Answer: Yes) First-off, they were not told that they were getting an effective drug. They were told they were getting either a placebo or a probably ineffective, experimental vaccine. So the subjects knew beforehand that this shouldn’t be considered a real vaccine.

Second question: why not just give the vaccine to everyone in the study (16,000 people) and compare the effectiveness to the general population? The problem is that you would have a change in HIV incidence that was due to lots of factors. Behavior, knowledge, unknown risk factors (maybe people at higher risk had a greater desire to be in the study than the general population) all could affect the measured efficacy. How would you know which produced your result?

If the vaccine were 100% effective, then there would be no need for a placebo controlled trial. But nothing is 100% effective and – besides – how would you know before you tried?

Now, here’s the more difficult bioethics question: if you have a 30% effective vaccine, who should get it?

This is more tricky. You don’t want to encourage risky behavior (the ‘conservatives’ are always concerned about this). So there is a question to be answered by a careful psychology study: do people modify their behavior after receiving a drug that may or may not prevent a transmissible disease? It seems like they might, but scientists don’t make decisions on “might” if they can avoid it. We make decisions based on what is demonstrably consistent with experiment.

But then it becomes a quantitative statistics problem (more statistics!). It’s only worth vaccinating people if their behavior changes don’t outweigh the efficacy. And then it’s only worth vaccinating people who are at risk… but what if the higher risk people are more prone to behavior modifications? Is is possible to isolate a medium-risk category?

And in all of this, there are massive political problems, not the least of which are form the anti-vaccination people, which I will talk about next week. The vaccine is a real achievement, in any case. Lots of people thought it wouldn’t work. And it reminds us how complicated it gets when trying to do the right thing with imperfect tools.


mercury and table salt

I want to briefly talk about mercury. Mercury is a metal found in nature. It is as natural as sea-salt. It’s a wonderful example of why the word “natural” is not the same as “good.”

How toxic is mercury? According to its Material Safety Data Sheet at Fisher Scientific, it has a toxic dose of about 400 mg per kilogram body weight. At that level it causes tumors in 50% of lab rats. Nobody wants tumors, so I don’t recommend coming into contact with mercury at all. But at the same time let’s put that in perspective.

Table salt has a lethal dose of salt (not tumors – death) only about 8 times as high. that’s right, 3000 mg of salt per kg body weight can kill you (~50% chance of living). Should you avoid salt? No, you need salt. Just don’t gag down grams of it.

Mercury? You don’t need mercury for anything. So avoid it, especially if you are considering having children in the next month or two. But at the same time, don’t freak out about it. Compact fluorescent light bulbs contain a few milligrams of mercury. The post to which I linked is ridiculous. For instance, it quotes a air quality standard of 300 nanograms per cubic meter (of air!) and extrapolates that to soil concentration. Absurd.

The big upshot is that exposure to mercury is an increased risk factor, but so is a well made burger.