TG-Matchmaking - we get unbalanced game bc elo calculation is wrong

Hi,
so most of us know that TG elo is kinda off and here is why:

Example of Players:
Team A: Team B
2500 2500
2200 2500
2800 2500

so this is even.
Case: Team A wins
The lowest player gets +15, and highest +2.

Case Team A loses
The lowest player gets -2, and highest -15

play 20 games like this (10 wins, 10 losses) and the 2200 player will gain 10x15=150 points and lose 10x2=20 points.

so he will be up 130 points after playing perfectly balanced games…

his elo now is 130 points off where it should be

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I made my own thread of finding the issue with team game elo.

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Ya, but MM is supposed to be randomly creating these games, so highly unlikely that he will play 20 games in a row that are above his ELO. Random games means that he will sometimes be over and sometimes under the average ELO of the game.

Even if he gets 20 games in a row with a higher ELO (again unlikely) then winning 10 and losing 10 means he deserves his ELO to increase a lot more than decrease. He didn’t break even at his level, he broke even at games higher than his ELO by 300 on average. This is not the problem with current ELO.

Many of us have noticed that we gain more points upon winning on average, than we lost upon losing on average. There lies the problem.

Another issue I hope devs would resolve when they (eventually, if ever) work on fixing ELO, is to make the starting/average ELO the same for 1v1 and TG. I can’t count how many noob games I got kicked out of, because the hosts get scared of my 1500 TG ELO, though it is the same as ~ 1000 ELO in 1v1. This is annoying.

Starting Elo is 1000 for 1v1 and team games.
But if you already have a 1v1 rating, than it will be used to adjust your team game rating. Same is true if you have already a team game rating. It will be used as starting point for 1v1.

The main issue is that team game ratings are for some reason inflated. Everyone gets more points than the loose. Based on the graphs 1350 TG Elo = 1000 1v1 Elo. TG rating is inflated by around 350 already and still inflate even further.

The question: Why do we gain more points than we loose, is still unanswered for me. I asked the same question in my own thread (Analyses of the ratings - Spotting the issues). No one really answered that question. I hope the devs know the answer and also know the fix. Otherwise ranked team games will be dead very quickly.

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thats as close as u can get to r/selfawarewolves 11

the games are BALANCED. he gets carried by the 2800. its not relevant if he is 300 elo under avarage, bc someone is 300 elo above average. hence his skill is 2200 and perfectly balanced in that game. He doesnt deserve to get more points.

He should only get more points if the average is lower. f.e 3x 2200 vs 3x2500.

Obviously there will be less high rated games (bc fewer high rated players) hence lower elo will get more often into higher rated games than the other way round.

Also it doesnt matter, bc my point is: Elo calculation isnt based on the average elo, but on the relative elo

a better formula would be sth like:
+/- 10 for win/loss of balanced games, +/- 10 for deviation of AVERAGE elo, +/- 5 for RELATIVE elo

the current formula is sth like:
+/- 0 for win/loss of balanced games, +/- 3 for deviation of AVERAGE elo, +/-20 for deviation of RELATIVE elo

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I play mostly team games and I’ve noticed that when your team wins the higher ranked teammates gain fewer points than the lower ones, and that when your team loses the lower ranked players lose fewer points. The gain/loss also depends on the other team of course, but the important point is that the algorithm compares your individual scores with the other team’s scores.

Here is the problem: Suppose you have one strong player teaming with one weak player. The algorithm is probably going to give them opponents with an average skill level somewhere in the middle. If the matchmaking is roughly fair*, they should win roughly half the time. But the strong player is going to be losing a lot more points each time (s)he loses than she gains when the pair wins, and the weak player is going to gain a lot more points with each victory than (s)he loses when they lose.

If they play multiple games their elo is going to converge, and the stronger player will effectively be giving away elo to the weaker player. This will of course cause mismatches in skill level if they ever decide to play with other teammates or enter the queue alone.


*You don’t actually have to assume fair matchmaking for this argument to work. Just note that the expected elo change is p(win) * gain - p(loss) * loss. Playing together means you have the same p(win) and p(loss), but the higher skill player will have a smaller gain and a larger loss, so there is no way both of these expectations can be zero.

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Yeah, the points you gain or lose is based only on the strongest player on the other team (99.7% sure) and your ELO. This is a big reason why ELOs are “inflated”. Played a game where we faced a 2700 and some smurfs/low rates, all the players on my team lost 0 points (1900 to 1400) while I’m sure all the other players gained a ton (other than the 2700).

Every player should theoretically get the same number of points on a team, only problem is that it will take way too long for decent players to get up to 2k which is where most decent players are these days.

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