The "Rehgar Effect" -Illidan version

If you apply the same logic to literally any other hero in the game, you will get the same results. Let me do the same logic and we'll see what we get:

  • Illidan has a 48.1% win rate overall. (15984 games, 7688 wins, 8296 losses)

  • Illidan has a 62.2% win rate with Rehgar. (5281 games, 3285 wins, 1996 losses)

  • Illidan has a 41.1% win rate without Rehgar. (10703 games, 4403 wins, 6300 losses)

Now here's what you missed:

  • Illidan has a 32.2% win rate against Rehgar. (4116 games, 1325 wins, 2791 losses)

So with this extra data that you so happily chose to ignore, we can also say that:

  • Illidan has a 46.7% win rate in games without Rehgar on either team. (6587 games, 3078 wins, 3509 losses)

Well there you go, then. Turns out you were right. Rehgar does indeed pull up Illidan's win rate. The Rehgar Effect - Illidan version is true after all. However, your number was a bit off. It's not by 20%. It's by a mere 1.4%. Now this is where I would say something profound, but I feel like the 1.4% speaks for itself.

But wait, there's more. Illidan has a 62.2% win rate with Rehgar, and a 32.2% win rate against Rehgar. This can also be phrased as Rehgar has a 62.2% win rate with Illidan, and a 67.8% win rate against Illidan. What this means is that Rehgar actually does better against Illidan than with him. But since there are more games of them on the same team than different teams (5281 games vs 4116 games), it actually favors Illidan and detriments Rehgar. We can also say that:

  • Illidan has a 49.1% win rate with Rehgar on either team. (9397 games, 4610 wins, 4787 losses)

So if (hypothetically) there were as many games of (Illidan + Rehgar) as (Illidan vs Rehgar), then we could take the average of his win rate with Rehgar and his win rate against Rehgar, and Illidan would have a 47.2% win rate. Which shows more accurately the effect that Rehgar has on Illidan's win rate (because it ignores the fact that Rehgar is more likely to be with Illidan than against him, since we're looking at Illidan and Rehgar objectively). So instead of a 1.4% difference, it's actually a 0.5% difference.

TL;DR: Realistically the numbers are so insignificant and the matchup & duo pages for hotslogs aren't entirely accurate, so the real conclusion is that Rehgar has virtually no effect on Illidan's win rate.

Now the real question is why do I bother to write this huge reply just because a person on reddit doesn't understand how statistics work.

/r/heroesofthestorm Thread