Go vs Tetris ranks

Most of you should have heard about Tetris. Similar to Go, Tetris has simple rules and high emergent complexity, and a wide skill gap between strong and weak players. Tetrio (one of the online Tetris servers) uses Glicko-2, which allows for comparison with Go ratings.

Inspired by the go-chess comparison threads, I have attempted to make an overall go-tetris rank comparison table:

Go rank Go rating Tetrio glicko Tetrio rank
Shin Jinseo 3700
Ke Jie 3600
Top 10 pros 3500 4200 Best player
Top 25 pros 3400 4079 X
Top 50 pros 3300 3959 X
Top 100 pros 3200 3838 X
Top 200 pros 3100 3718 X
9 dan professional 3000 3597 X
7 dan professional 2900 3477 X
4 dan professional 2800 3356 X
1 dan professional 2700 3235 X
6 dan 2600 3115 X
5 dan 2500 2994 X
4 dan 2400 2874 X
3 dan 2300 2753 X
2 dan 2200 2632 X
1 dan 2100 2512 X
1 kyu 2000 2391 U
2 kyu 1900 2271 U
3 kyu 1800 2150 SS
4 kyu 1700 2029 SS
5 kyu 1600 1909 S+
6 kyu 1500 1788 S
7 kyu 1400 1668 S-
8 kyu 1300 1547 A
9 kyu 1200 1426 A-
10 kyu 1100 1306 B+
11 kyu 1000 1185 B-
12 kyu 900 1065 C+
13 kyu 800 944 C
14 kyu 700 824 C
15 kyu 600 703 C-
16 kyu 500 582 D+
17 kyu 400 462 D
18 kyu 300 341 D
19 kyu 200 221 D
20 kyu 100 100 D

*Go rating as on goratings.eu, or approximately goratings.org elo minus 100

(obligatory remark)

Both using glicko2 does not mean they are comparable.

Also, I’d expect these two pools to be rather uncorrelated

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I agree it would be rather uncorrelated, this is a comparison of the amount of combined time, effort, skill and talent required for each level, and most people won’t be equally devoted to or have equal talent in these two games.

Isn’t Glicko2 supposed to be used in one-to-one matches situations?
Is tetris so?

I’ve seen arcade games where you could play tetris against an opponent, but I always thought that Tetris way of working was related only to one person’s skills. I don’t see how your score could be affected by your opponent’s score.

Am I missing something?


This is an example of 2-player Tetris, from the grand finals of a recent tournament. To win you need to do difficult clears (Tetrises, T-spins, all clears and combos) to send garbage (the grey blocks), which will kill your opponent if it pushes them up to the ceiling.


Those amateur go ratings look like EGF ratings, which are not Elo ratings (nor Glicko ratings), because they are defined/calculated differently. It’s mostly coincidence that the lower pro ratings from goratings.org line up (more or less) with the higher amateur (~7d) EGF ratings.

Is it a coincidence? I believe the EGF ratings use a variation of the Elo formula, and have been parametrised specifically to fit kyu/dan ranks. So it looks more a design decision and less a coincidence?

Yes, those are design decisions. But some of those decisions are arbitrary, so I consider a rough match between EGF and WHR (goratings.org) around 2700 rating mostly coincidental.

Rating gaps have a clear meaning, both in EGF ratings and WHR. But the meaning of a rating gap is not the same in both systems. In EGF it means handicap for 50% winrate, in WHR it means winrate in even games (as in OGS rating system and regular Elo rating systems).

Absolute ratings are determined by the rating anchor chosen by the creators of the system. In the EGF rating system, Ales Cieply decided around 1995 to define absolute EGF rating = 2000 + dan * 100. So 1k = 2000, 1d = 2100 and 7d = 2700. This is fairly arbitrary. He could just as well have chosen 3000 or 1000 for 1k. I think he chose 2000 to have ratings in a similar range as chess Elo ratings for “fairly competent club player level”.

Ales’ decision to fix 1 rank gap to 100 EGF rating gap was probably influenced by the previously known observation that around EGF 1d, 1 rank gap corresponds to about 2:1 odds to win an even game, which corresponds nicely to an Elo rating gap of about 100 points. I think Ales just exploited this coincidence (serendipity?) in making EGF ratings similar to chess Elo ratings around 1d level.

Chess rating systems often use 1500 as the initial Elo rating for players new to the system. Because of that, 1500 is the rating anchor for most chess rating systems (at least it used to be). It corresponds to the typical chess player (intermediate level). OGS does a similar thing, and currently OGS rating 1500 corresponds to aboutk 6k, which would be a typical OGS player.

I don’t know what rating anchor Rémi Coulom chose for his WHR ratings. Maybe he chose 3000 as the initial rating for players (pros) in his system?


I remember reading somewhere (but I can’t find it now so don’t take my word for it), that goratings were originally anchored much lower, but then there were complaints that pros were not rated “high enough”. So Rémi simply added 1000 points to all the ratings :smile:

On the one hand, this is a funny example of people not understanding the relative nature of a ranking system. On the other hand, if they were trying to compare the numbers to EGF ratings, it’s no longer a total coincidence that there is now a point where the systems line up.