By the way, I am not the only person to have published these findings. Some Blizzard employees did a slideshow presentation wherein they said the correlation between APM and win-rate was 0.63 (if memory serves). There are other papers (link below) which show the correlation between MMR and APM to be 0.65. I once calculated how much APM can vary on a per-individual basis for the corr(Winrate, APM) == 0.65 to be true. In 95% of cases, a player’s APM will vary from what’s predicted by their win-rate by no more than 26 APM. It’s simply a fact that APM is the majority of the skill in the game.
Side note: at the time I made that calculation, I didn’t have access to mass replays for data mining. I calculated that off of the figures from the slideshow, an average APM table for each league, and the assumption that APM was normally distributed. Well, this paper confirms my calculations (congats to past batz) and shows my assumptions were justified (congrats again to past batz). Source:
I’ll add a quick sub-note to this. This is calculated for players in masters league under the assumption that corr(MMR, APM+scattering)=0.65. When calculated for the ladder as a whole, the result is Scattering ~ N(0, 65). To contrast my simulation against the data in the paper I referred to previously:
https://i.imgur.com/QfIlmxx.png
As you can see, it’s spot on.
I’ll add another sub-note. Because MMR is a very dynamic system and players’ mmr values are always fluctuating up and down, it’s likely the vast majority of the variability in this correlation is due to the instability of MMR and not APM. I don’t have any figures on the variability of MMR so I don’t know exactly how much to attribute to it but we do know the correlation between average MMR and average APM is certainly > 0.65. It’s probably something like 0.8.