But consider the leaders specified for groups of Men in OD&D Vol-2; recall that it asserts for Bandits and likewise all other types of Men:
BANDITS: Although Bandits are normal men, they will have leaders who are supernormal fighters, magical types or clerical types. For every 30 bandits there will be one 4th level Fighting-Man; for every 50 bandits there will be in addition one 5th or 6th level fighter (die 1-3 = 5th level, die 4-6 = 6th level); for every 100 bandits there will be in addition one 8th or 9th level fighter (die 1-3 = 8th, die 4-6 = 9th).
So, 4th level fighters appear in a ratio of 1/30 = 0.03; 5th-6th level fighters in the ratio 1/50 = 0.02; and 8th-9th level fighters in the ratio 1/100 = 0.01. Let's compare that to the numbers that fall out of our Arena simulator above:
At the first step and the last step, the results match surprisingly, almost supernaturally, well. At the middle step the simulator asserts there should be about twice as many 5th-6th level fighters combined, as compared to the book rule. But nonetheless the book ratios constitute a basically reasonable distribution, and our simulator generates roundly the same kind of population. (Remember that this is not the same as the population of adventurers exploring underworld dungeons, which is exponentially more dangerous.)
This, then, motivates the development of another software tool that you'll see here on Monday.