Player rating for tournaments across all installments of Heroes.

I'm talking about tournaments without so many newcomers.

Added after 12 minutes

In the second tournament, there are fewer strong players, so a weaker player has a better chance of placing closer to the leaders.

Wouldn't this work?
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Or maybe we should just calculate the total rating of all participants in the tournament and divide it by the number of participants. This would be the coefficient. Maybe it would be simpler for calculations.
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Where it's higher, it means it's more difficult to play for anyone.