Cause and effect in the UK’s “top” universities

As a scientist I know that correlation does not imply causation. Just because two things, A and B, are correlated does not imply that A causes B or vice versa. For example, there is a correlation between the number of pirates on the world’s oceans, and global temperature, but this does not imply that pirates, or their absence, is causing global warming. But even if there is cause and effect going on, then you still have to work out if A causes B, or if B causes A.

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All models are wrong, unless you have limited data, in which case most models are right

I am very fond of the quote by the statistician George Box: “essentially, all models are wrong, but some are useful”. It is true, all our models are wrong if you look carefully enough. For example, Newton’s model of gravity is pretty good for calculating our orbit around the Sun, but if you look carefully enough you will see it is wrong. Careful measurements and general relativity have told us that it is an approximation. The same thing applies to pretty much every model we have.

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