Better document the 'mr' parameter to 'metrop_select'.

[bangerth]

I found myself confused why metrop_select() has this comparison:

    if np.isfinite(mr) and np.log(uniform()) < mr:

If mr was just a ratio of probabilities, as one would typically see in theoretical descriptions, then it should be compared to uniform(), not the log. But mr is the logarithm of the ratio -- something not clear from the documentation, but that can be added :-)

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📚 Documentation preview 📚: https://pymc--7160.org.readthedocs.build/en/7160/

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