How do you calculate %xHKO?

If it is within my capacity to do, I would like to know how. Also, it is possible to have it work with crits? I know it's hard, as Stereo said, but I'm very much interested in making a hits to kill calc for all most classes.

If I see it correctly, one should be able to use it with N different damage-"ranges", where N is 1 or higher. Assume that all these damage ranges have the Range R_n and the probability P_n to occur (It will work with a constant damage, such as 0 or so, or with a probability of 1 or 0).

I thought about Convolution first, then I found out that IFS have a better potential when using combining probability mass functions and probability density functions, and then take the integral of the lower limit (monster's HP) after iteration. Sounds kinda messy right now, as I've not got time to think much about it, as well as exams going on now. Hopefully some of that made sense.

Noah