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Sorry, but you seem to be suggesting that non-response bias would be responsible for the uniform distribution seen in the Update mileage digits as well as the uniform miles driven distribution?

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Theoretically, yes. I’ve used stratified sampling in this kind of research, since the underlying portfolio is so skewed.

I really don't see how any random sampling mechanism (unless you're literally stratifying based on the last digit of the odometer) would cause these sorts of results, please explain further.

Or, even better share the data you reference from "this kind of research".

These are customers they already know I presume. So they have an inkling of the expected mileage (at least: we price on expected mileage). So you repeatedly sample dropping some samples to get enough filling in all mileage baskets. It’s a stratified sample and random.

Say you have 10k customers with 1k women. You want to take a sample And want enough power to get answers on women. In that case you do stratified sampling.

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