ELO loss after a perfect game

[Not Anubis]

Has anyone encountered this? We finished a perfect 30/30 game, no one conceded or left, and at the end I lost 1 ELO point.

[Jellby]

If the average elo of the team was above the "bot elo" for your particular settings, that's expected.

[Travis Hall]

If the average elo of the team was above the "bot elo" for your particular settings, that's expected.

Even wth a team mean rating above the highest bot rating for the settings, you shouldn’t lose rating points with a perfect score. According to this:
https://en.doc.boardgamearena.com/Gameh ... ELO_rating

… a perfect score should be calculated as if a win against the bot, and a win should never result in a decrease of rating.

Possibly the algorithm has been changed since the calculation description was written, but if players are losing points on a perfect score, there’s a problem with what has been implemented.

[Travis Hall]

But also, with ELO display currently disabled for Hanabi, how are you sure that this has happened?

[ufm]

The current rating can be monitored on game page and game start waiting screen

[Jellby]

I suspect the info in the wiki is inaccurate. Maybe written by someone who doesn't really know what's going on (I don't claim I do), or based on an older version. In my experience, at least until the latest "hidden elo" changes, it is always assumed a tie with the bot, perfect score or not. The wiki also says "Hanabot's ELO = 1000 with scores < 18 (5 colours) and < 21 (6 colours)", which doesn't seem correct, maybe it means 100 instead of 1000?

PS. You can get your elo change if you check your elo before and after the game (e.g. in the "old lobby" screen).

[Not Anubis]

But also, with ELO display currently disabled for Hanabi, how are you sure that this has happened?

Right before the game started I made sure to check my ELO rating on the main page, and it went from 820 to 819.

The only other explanation I can think of is maybe a previous loss from several games ago didn't register immediately.

[ufm]

I suspect the info in the wiki is inaccurate. Maybe written by someone who doesn't really know what's going on (I don't claim I do), or based on an older version. In my experience, at least until the latest "hidden elo" changes, it is always assumed a tie with the bot, perfect score or not. The wiki also says "Hanabot's ELO = 1000 with scores < 18 (5 colours) and < 21 (6 colours)", which doesn't seem correct, maybe it means 100 instead of 1000?

PS. You can get your elo change if you check your elo before and after the game (e.g. in the "old lobby" screen).

It means standard ELO value used until 2019, not BGA value adopted after 2020. So, old 1300 = new 0.

[Sammy McSam]

The meaning of the ELO rating section has been unchanged since the help page was created by beri 2014-11-18T18:14:21:

ELO rating

If you are playing with ELO rating on, your ELO may be changed at the end of the game.

Here is how it works:

1) Every player on the team is temporarily considered as having the average ELO rating of the team.

2) The system will generate a bot associated with the score your team has achieved (let’s call it Hanabot). Hanabot’s ELO rating depends on the variant you are playing (50 cards, 60 cards, 60 cards multicolor), the number of players on the team and, most importantly, your team's score. All Hanabot’s ELO ratings have been set by an experienced player, they are not random or simply proportional to the score/number of players.

3) Your team (actually your team's average ELO) will now compete against Hanabot. The system will calculate your team’s ELO gain/loss as though your team had tied with Hanabot. If your score is below 18 (50-card game) or below 21 (60-card game), your team is considered as losing against the weakest Hanabot for this configuration (variant and number of players).

FYI, you can find all ELO ratings here: <link to be inserted>.


The 55-card variant (50 cards + 1 of each value in the sixth colour) cannot be played with ELO rating on. This is because this variant is highly dependent on draw and a team’s score may not always reflect the players’ skills.


A loss (3 Strike tokens) is the same as a score of 0.


If you achieve the perfect score and this should cost you ELO points, you will be considered as having beaten the bot associated with the score, so that you lose no ELO points.

2014-11-20T16:27:04 beri changed

your team is considered as losing against the weakest Hanabot for this configuration (variant and number of players).

to

Hanabot's ELO is always 1000.

2017-09-05T20:56:23 Gamersktrashcan added

To be confirmed: I think the ELO-system has had an overhaul.

[Sammy McSam]

From the ELO rank changes in 2017:

How did you convert old ELOs into new ones?

If you have 0 games played: new ELO = 0.
If you have more than 4 games played: new ELO = old ELO - 1300, with a minimum of 100.
If you have between 0 and 4 games played: new ELO = old ELO - 1300, with a minimum of 1.

I've replaced 1000 with 0 on the help page.