Quote of the day 23rd August 2022

Stop and think about this quote. The point that economist Thomas Sowell is making here about the conclusions we may draw from data is not at all obvious - some might even call it counterintuitive. But it is true. 

Statistical evidence can be very useful in checking theories against the real world. But the real world is more complicated than any theory.

Sometimes the manner in which things work at the micro level can look like the opposite of what is really happening when you aggregate the data together and just look at the the macro level (or top level) data.

In some circumstances the same can be true the other way around. 

When either of these things happens, or any similar statistical freak, the hardest thing to do can be to establish which conclusion is right, and the worst thing to do is to dash ahead with your original view quoting the data in the form which suggests the conclusion you want in support. Because in that case the most likely explanation is that either conclusion can be right in particular circumstances.















Postscript - I gather that the image with the Thomas Sowell quote: "The same set of statistics can produce opposite conclusions at different levels of aggregation"  -  did not display properly for some  readers of this post in it's original form. I hope this is clearer and apologise for the inconvenience.







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