Any Probability/Statistic majors among us?

[Nystul]

Here is what I call "The Amazing Brute Force Solution":

rog/az
rog/snow
rog/spawn
rog/soul
az/snow/spawn
az/snow/soul
az/spawn/soul
az/doom
az/steel
az/magi
az/cabal
snow/spawn/soul
snow/doom
snow/steel
snow/magi
snow/cabal
spawn/doom
spawn/steel
spawn/magi
spawn/cabal
soul/doom
soul/steel
soul/magi
soul/cabal

total possible combos for level 15 = 24
odds for rog = 4/24 = 1/6
odds for az = 8/24 = 1/3
same odds for the knight or lawyer types as for rog
same odds for the witch types as for az
Resulting percentages match Jarulf's Guide.

Interestingly, this method could be derived empirically through game experience without any knowledge of "monster size" data.

Perhaps a real stat wiz can provide a more elegant solution.