Category Archives: Science

On Climategate

As you know, emails leaked (read: stolen) from a climate research group suggested some inappropriate attitudes amongst the scientists – at least when carefully edited and comber for inflammatory material. Review by major publications found that the emails did not constitute evidence of fraud, but the public perception was quite the opposite.

Of course, lots of people are emotionally invested in climate research. If it’s true, a lot of our habits will have to change. If it’s not true, it is a very expensive mistake. Furthermore, lots of scientists have staked their careers on propositions that it’s a big deal. So, yes, there is a bit of incentive to defend that proposition. But a lot of the public discussion concerns the “consensus” among “scientists.”

Wrong question: “do scientists believe in global warming?”

Right question: “do specialists in the field of climate science find a credible risk?”

With regard to the second question, there is an answer. There is consensus. Yes, there is a risk. Consensus does not equal truth, of course. Nor does credible risk imply a guaranteed catastrophe. Nor does outright fraud imply a bankrupt field. Let me explain these three.

Consensus is not truth. If you had asked a well-educated ornithologist to describe swans a few hundred years ago (prior to 1790), he would have told you about white, majestic birds. There was consensus based on thousands of observations that all swans are white. This was credible science based on good evidence and it would be wise to respect the conclusion as the best given the available evidence. It was entirely wrong, of course. There are black swans. But a consensus based on the preponderance of evidence is often the most trustworthy guideline available, and we would be foolish to discount them because they might be disproven tomorrow. Of course, we must keep collecting data, and we must be prepared to throw out formerly cherished beliefs if the data contradicts them.

Credible risk does not imply a guaranteed catastrophe. It’s a risk. Like in gambling. And lots of people are trying to estimate the odds. There is some pressure to estimate high – that gets the headlines. There is another pressure to make the estimate high: the precautionary principle. An editorial in the WSJ gave this version: “precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.”
The precautionary principle is reasonable for governments and individuals, but not for scientists who are actively trying to fully establish the cause and effect relationships. Those relationships determine the risk, and we have to be honest about them. We don’t get to cheat and say “as a precaution, I estimate the risk to be 90%”
If the best estimate of the risk is 10%, that may not scare people enough. It doesn’t matter – we still have to report 10%. Let the politicians explain why avoiding a 10% risk of total economic shutdown is a lot more important than a 99% risk of inconvenience. But that principle only applies to the evaluations of the conclusions, not the interpretation of the data. Did the East Anglia fall into this trap? I have no idea, but at least that is a legitimate worry.

Isolated fraud should not discredit the whole community. To be clear, these emails do not constitute fraud. But, even if they were, and a retraction of a publication was required, that’s not the same as the whole conclusion being false. If a gold medal sprinter turns out to have used steroids, we don’t conclude that all fast people are dishonest, and that it’s impossible to run fast. There was an incident a while back where a Korean researcher claimed some amazing breakthroughs with stem cells. It was completely fabricated. Some time later, other groups actually did much of what he falsely claimed to have done. Just because one guy cheated didn’t make the achievement impossible. It was just really hard.

What we have with climate change is a consensus based on available data that there is a credible risk to humans due to anthropogenic climate change. A few people have gone to lengths to present this in a black-and-white manner. I suspect that they were trying to strip ambiguities because of a decent moral impulse (the precautionary principle) without considering the proper distinction between interpretation (assessing the risk) and evaluation (determining the appropriate response to that risk). When scientists do that, they erode the credibility of science in general, as an opinion piece in the WSJ points out. But, then, this sort of philosophizing isn’t really stressed in our training. Maybe it should be.

Cheers,
Peter

Wired article on a 1982 artificial heart

Wired has an article today on the first use of an artificial heart back in 1982. The patient survived for 112 days – pretty remarkable. I wonder if he felt any unnatural urges toward appliances… robot love, as it were. I doubt it. It sounds like it was a pretty miserable 112 days. I suspect that subtle emotional changes toward toasters… or uncomfortable fantasies about R2-D2… were secondary concerns.

Despite the derision with which the heart’s mystical associations have been dismissed, it’s a rather complex organ with a great many feedback mechanisms to keep it precisely regulated. We’ve come a long way in 30 years. In addition to thinking in terms of an improved plastic pump, there is a lot of thought going into manipulating stem cells to make new hearts from meat, the way nature intended.

-Peter

Directed Evolution: macro and micro scale

I work in a lab now that focuses on directed evolution. We typically look at a huge, diverse pool of molecules and then select and “breed” them to get molecular properties we want.

This is something that can be used on the macro scale, too. In thinking about diseases, it’s important to consider not just a patient, but the population dynamics of the pathogen. Malaria, for instance, can be exacerbated or ameliorated by the preferential treatment given to severe cases. If sever cases are allowed to go untreated and the victim is allowed to be visited by mosquitoes, then the most severe forms become more likely.

Constant vigilance in removing severe cases from the population by something as simple as bed nets for every sick person can dilute the population of virulent forms of the disease. Tricks like these are undoubtedly going to be more and more important as diseases learn to avoid our chemical cures.

Here’s a neat article on the subject over at Nature

Cheers,
Peter

Believing we are right: Why Dr. House is a good role model

Humans, doctors and grad students included, are all prone to rationalization. This can be a good thing. Think about that TV show House, M.D.. The main character is not always right, but he always is totally convinced of his own opinions. If you think about that, it’s pretty remarkable.

When his opinions are refuted by hard evidence, he drops them without remorse. But up to that point, he is sufficiently certain to risk your life on the basis of his conviction. That’s actually a pretty good thing, in the following sense: if he were unwilling to change his opinion after finding new evidence, he would be an extremely dangerous person to have as a physician. By a similar token, if he wanted conclusive proof of a given diagnosis before starting treatment, he would lose patients because they would die before he was certain.

The following formula is reasonable: get the information you can and act decisively on that until better information is available. But it’s only reasonable so long as you keep the information channels open. That’s why Dr. House is a good role model. Despite being a jerk and despite seldom acknowledging that he was wrong, he never persists in a wrong opinion once it’s disproven.

The problem is that we are prone to rationalize the facts based on the diagnosis we had before. Take people who still believe that Saddam Heussein was involved in the September 11 attack. Presented with new evidence, many people will choose to ignore or rationalize around that evidence in order to preserve their old, erroneous conclusion.

And with just a few simple, mental sleights-of-hand, we can preserve that belief. Here’s another fine example: form the NYT, an Iraqi official purchased several million dollars worth of totally useless “electrostatic magnetic ion attraction” detectors that are billed by the manufacturer as being able to detect bombs and ammunition. A few simple tests are sufficient to show that they are capable of no such thing.

Why would someone believe something patently false in light of clear data to the contrary? Before we get all proud about how we are different from them, those other people, I would offer the following words of caution: believing that we are right is seductive to all of us. The only shared standard against which anyone can test his opinions is the physical world and the data that comes from it and that’s not an easy standard to uphold.

Cheers,
Peter

I.Q. and Wisdom for Pre-Med: worry less about your MCAT

Today’s Big Upshot concerns IQ. I’m not going to do this as well as Malcolm Gladwell who has a great section in his book Outliers: The Story of Success. But, nonetheless, I think it’s worth talking about in the context of a discussion of medical careers. It might be presumed that I.Q. measures intelligence and that intelligence is an important quality in a physician. If intelligence is the brightness of your mental spotlight, then in diagnosing disease it would probably be good to have lots of it.

However, it is at least as important to be concerned with where that spotlight is pointing as it is to have it be very bright. I hope everyone has head the med-school-admissions-anomaly stories (i.e. “this happened to a friend of a friend”). There was this guy who got a 4.0 GPA in college and got a perfect MCAT score and then went to his med school interviews and didn’t get admitted to any of the schools to which he applied. He ended up working at Kaplan, teaching kids how to do well on their MCAT. Weird, huh? If you have not met this guy, you probably will. There’s one in any big school’s pre-med program at any given time. You won’t see much of him, though, because he has a 16 hour a day study schedule

The guy is smart. He has a high I.Q. But the admissions committee knew better than to let him in their institution’s door. They knew that a certain degree if wisdom is prerequisite to be a decent doctor.

Gladwell tells a great tale about a large-scale study of I.Q. in California kids. The researchers followed the fates of these super-smart kids through their lives. Their fates turned out to be remarkable only in their ordinary-ness. These super genius kids did not turn out to be the captains of industry and leaders of tomorrow. In fact, most telling, there were two Nobel prize winners in the original, large sample. They were dropped from the study because their I.Q.s were not high enough.

The New Scientist has an article up this morning that explores come clever ways of testing another aspect of cognitive ability – the analytical, careful reasoning side. What the article really stresses (correctly, in my estimation) is that high I.Q. is only useful if it is fully engaged on the problem at hand. What’s scary is that for lots of questions in life and on tests, people (even really smart people) don’t fully engage their careful reasoning abilities.

So, here’s my point – the Big Upshot, if you will. Tests do help open doors – they validate other achievements, in a way. If grades are grossly disproportionate to SAT or MCAT scores, it might be a red flag. But a standardized test score is only one data point in the minds of any admissions committee, and they’re the only people who care at all. Frankly, a personal connection of any kind trumps any score hands-down. So if you’re pre-med (or on an admissions committee, for that matter) keep that in mind. Being wise enough to really engage with the right questions is at least as important as having the strongest possible abilities which could (potentially) be engaged.

Cheers,
Peter