How to interpret scientific claims – 20 tips

How should one interpret scientific claims? Here are the headings to an excellent article featured in Nature: Differences and chance cause variation. No measurement is exact. Bias is rife. Bigger is usually better for sample size. Correlation does not imply causation. Regression to the mean can mislead. Extrapolating beyond the data is risky. Beware the base-rate fallacy. Controls are important. Randomization avoids bias. Seek replication, not pseudoreplication. Scientists are human. Significance is significant. Separate no effect from non-significance. Effect size matters. Study relevance limits generalizations. Feelings influence risk perception. Dependencies change the risks. Data can be dredged or cherry picked. Extreme measurements may mislead.

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Robert Sapolsky discusses the alleged uniqueness of humans

Excellent lecture by Robert Sapolsky. Scientists used to think that humans were unique in many ways when compared to other animals. The number of ways in which we are truly unique is dwindling, however, and that dwindling number is the focus of Sapolsky's talk. There is at least one way in which we are unique, and that is our ability to entertain a contradiction. Sapolsky, speaking to a graduating class, challenges them to take on this contradiction: They are highly educated and thus privileged human animals who are educated to such an extent that they realize that it is virtually impossible for one person to make a difference in the world. The more clear this becomes that it is impossible to make the world better, "the more you must."

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The beginnings of multi-cellularity

Fascinating story told by Carl Zimmer, illustrated by yeast studies.

Scientists suspect that the first step towards a complex multicellular body like ours is for cells to evolve to live in primitive clumps. There may be a lot of advantages to living this way. It may be harder for a predator to eat you, for example. At the University of Minnesota, a team of scientists led by William Ratcliff and Michael Travisano figured out a way to create this kind of natural selection in a lab. As I reported last year in the New York Times, they were able to get yeast–which normally lives as single cells–to turn into simple multicellular clumps in a few weeks.

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