Sunday 11 January 2015

WHEN DOES "EVIDENCE-BASED" BECOME CARGO CULT SCIENCE?

I've been asking myself "what is science"? "How can I separate real science from misleading evidence-based research? This 40-year old essay by Richard Feynman has some good pointers. 

He describes certain educational and psychological studies as cargo cult science.  And asks: "Do they work?"


Cargo Cult Science

Richard Feynman

From a Caltech commencement address given in 1974 
Also in Surely You're Joking, Mr. Feynman!




So I found things that even more people believe, such as that we have some knowledge of how to educate. There are big schools of reading methods and mathematics methods, and so forth, but if you notice, you'll see the reading scores keep going down--or hardly going up--in spite of the fact that we continually use these same people to improve the methods. There's a witch doctor remedy that doesn't work. It ought to be looked into; how do they know that their method should work? Another example is how to treat criminals. We obviously have made no progress--lots of theory, but no progress--in decreasing the amount of crime by the method that we use to handle criminals.
Yet these things are said to be scientific. We study them. And I think ordinary people with commonsense ideas are intimidated by this pseudoscience. A teacher who has some good idea of how to teach her children to read is forced by the school system to do it some other way--or is even fooled by the school system into thinking that her method is not necessarily a good one. Or a parent of bad boys, after disciplining them in one way or another, feels guilty for the rest of her life because she didn't do "the right thing," according to the experts.
So we really ought to look into theories that don't work, and science that isn't science.
I think the educational and psychological studies I mentioned are examples of what I would like to call cargo cult science.

Integrity! Yes! And honesty! And leaning over backwards! That is certainly convincing:
There is one feature I notice that is generally missing in cargo cult science. … It's a kind of scientific integrity, a principle of scientific thought that corresponds to a kind of utter honesty — a kind of leaning over backwards. For example, if you're doing an experiment, you should report everything that you think might make it invalid — not only what you think is right about it; other causes that could possibly explain your results; and things you thought of that you've eliminated by some other experiment, and how they worked — to make sure the other fellow can tell they have been eliminated.
Details that could throw doubt on your interpretation must be given, if you know them. You must do the best you can — if you know anything at all wrong, or possibly wrong — to explain it. If you make a theory, for example, and advertise it, or put it out, then you must also put down all the facts that disagree with it, as well as those that agree with it. There is also a more subtle problem. When you have put a lot of ideas together to make an elaborate theory, you want to make sure, when explaining what it fits, that those things it fits are not just the things that gave you the idea for the theory; but that the finished theory makes something else come out right, in addition.
In summary, the idea is to try to give all of the information to help others to judge the value of your contribution; not just the information that leads to judgement in one particular direction or another.
Emphasis mine.

Scientists who show that they do not fool themselves, and do not to fool the layperson are convincing: 
But this long history of learning how to not fool ourselves--of having utter scientific integrity--is, I'm sorry to say, something that we haven't specifically included in any particular course that I know of. We just hope you've caught on by osmosis.
The first principle is that you must not fool yourself--and you are the easiest person to fool. So you have to be very careful about that. After you've not fooled yourself, it's easy not to fool other scientists. You just have to be honest in a conventional way after that.
I would like to add something that's not essential to the science, but something I kind of believe, which is that you should not fool the layman when you're talking as a scientist. (...) I'm talking about a specific, extra type of integrity that is not lying, but bending over backwards to show how you're maybe wrong, that you ought to have when acting as a scientist. And this is our responsibility as scientists, certainly to other scientists, and I think to laymen.
Feynman also writes about the importance of putting sand in lab rat cages ... I'll let you find that in the link. And he ends with a wish that I send out to all researchers: 
So I have just one wish for you--the good luck to be somewhere where you are free to maintain the kind of integrity I have described, and where you do not feel forced by a need to maintain your position in the organization, or financial support, or so on, to lose your integrity. May you have that freedom.




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