Maybe that the natural frequency "normatized" for some people may be completely different from the actual frequency that apply to them, because the people that researched the frequency did their grouping badly.
I'm not sure if that's relevant. It seems like either you know the actual frequency for their subgroup, in which case you redo the numbers in the example, or you don't in which case you can't accommodate that regardless of how you calculate.
A natural frequency is different way of expressing and reasoning about the same information as percentages.
Well, me neither. If you get the frequency wrong, you'll also get your priors wrong. Natural frequency does not compose well, but that is another problem.
