Developer Insights: Hearthstone Battlegrounds Rating System Update
To complete the flurry of posts today, there is also this Dev Insight post about the Battlegrouunds Rating System Update. Delve into the details below!
Quote from BlizzardGreetings! I’m Tian, a Lead Data Scientist on the Hearthstone team. In 18.4, we are updating our Battlegrounds rating system and I’m here to talk about some science behind it!
Before I get into it, check out our previous blog on Battlegrounds rating if you’re interested in understanding the basics about personal rating and what it represents, how it’s updated after each game, and how variance works.
Now, let’s go to the main topic—the new rating system!
What are the motivations behind updating the rating system?
We want our rating system to both provide a sense of progression through gameplay and create fair matchmaking. It’s very hard to achieve these two things simultaneously by using only one rating. Therefore, we designed a “dual-rating” system to address our intention. In the updated rating system, there are two ratings—external rating and internal rating:
- External rating: this rating is shown in your Battlegrounds lobby interface. The main purpose of this rating is to provide seasonal “progression”, as well as partially or fully reflect your actual skill.
- Internal rating: this rating is invisible to you. The main purpose of this rating is to help us estimate your actual skill at all times and thus create fair matchmaking.
What are the updates on the external rating (player facing)?
- Your external rating is reset to 0 at the start of each season (18.4 is the start of the first season).
- There is a rating “protection zone” at the start of the season—you are not able drop external rating if it is below or equal to 2000. Therefore, rating 0 is the minimum possible rating you would see on your user interface.
- There are rating “floors” between 2000 to 6000 for external rating. Your external rating does not drop below each “floor” once it’s above it. Currently there is a floor every 500 rating: 2000, 2500, 3000, 3500, 4000, 4500, 5000, 5500, 6000.
- Your maximum external rating gain per match is 300.
- After each game, if your external rating is below 6500, we will give you a very small value of positive rating gain, on top of your “actual” rating change, which could be either positive or negative. For example, in theory your rating would be added/subtracted by 50 after a game, but since we give you 3 progression points, in reality your rating value will be added/subtracted by 53/47. That small value is determined solely by your external rating—the smaller your external rating is, the bigger this “progression value” would be. Note that this number is so small that you won’t even feel it unless you play many games. When your external rating is above 6500, this value is set to 0.
What are the updates on the internal rating (under the hood)?
Your internal rating, which is invisible to you, will never get a seasonal reset like the external one.
The overall distribution of the internal rating should follow a bell-shaped curve – in mathematics terms, “normal distribution”. We might enforce this distribution by performing a procedure called “re-normalization” to your internal rating from time to time. Such adjustments are usually very small but necessary!
The internal rating is not limited to any rating protection zones or rating floors like the external one, and there are no progression factors being added on top of that. You and your opponents’ internal rating and variance are updated completely based on your game result.
How is matchmaking affected?
We will match players based on their internal rating only, as it is designed to always truly represent your actual skill. During the match building phase, we will try to select eight players with the closest internal rating to ensure the match is as fair as possible for everyone.
Meanwhile, external rating plays no role in the matchmaking process. Therefore, it is possible a player with 7000 external rating is in the same game as a player with 1000 external rating, if their internal rating values are close. If you see a player with 0 rating in a high level Battlegrounds game, it’s because they have a high internal rating and are likely just getting started with the Battlegrounds season!
How do external rating and internal rating interact with each other?
As everyone starts the season with 0 external rating, and matches are “fair” in terms of skill, generally we want players with higher internal ratings to receive more rating gain after each win, while keeping the amount of rating lost after each loss the same for everyone.
Specifically, when your pre-calculated rating gain is positive, it would be multiplied a factor called a “rate gain modifier”. This modifier is proportional to the discrepancy of your internal rating and external rating, when your internal rating is larger than your external rating. You can think of this as a “chasing” process, as the external rating is “chasing” the internal rating. If your external rating exceeds your internal rating, the chase stops.
We hope you enjoy Hearthstone Battlegrounds! We are constantly listening to your feedback - feel free to share any matchmaking and rating comments with us. We’ll see you all in the Tavern!
"After each game, if your external rating is below 6500, we will give you a very small value of positive rating gain, on top of your “actual” rating change, which could be either positive or negative. For example, in theory your rating would be added/subtracted by 50 after a game, but since we give you 3 progression points, in reality your rating value will be added/subtracted by 53/47. That small value is determined solely by your external rating—the smaller your external rating is, the bigger this “progression value” would be. Note that this number is so small that you won’t even feel it unless you play many games. When your external rating is above 6500, this value is set to 0. "
This actually seems to either be false or something is broken in what they intended. Currently sitting at 5,500, got second in a game and it said I would get +74 mmr and instead I got +71 to my total. Then later I won, it said I would get +104 and instead I got +101. Maybe it's because I was doing good and the value went negative before it should have?
I'm at rating 1148 and have had ten 7th or 8th place finishes in a row. Great matchmaking system Blizzard, really fair. You know what - you can find another sucker to spend $$ on your game to be bullied around b/c they aren't good at the game. FUCK YOU and you perpetuating online bullying, scumbags. And your hero skins suck.
Not one new playable hero in all those games. Also "After each game, if your external rating is below 6500, we will give you a very small value of positive rating gain, on top of your “actual” rating change, which could be either positive or negative." Is bullshit. I've gotten 0 points each time despite trying and playing all the way through.
All you fanboy trolls that are going to attack me, I know I suck. That's the fucking point. I should be able to play against others that suck too.
If you're a bad enough player, then no matchmaking system is going to be able to find opponents that won't be likely to beat you. Just sayin'.
It doesn't make sense that they give you fake data with the hidden mmr, why don't they show the real mmr?
to keep us playing, if they reset it it's like we paint a wall blue and they come behind us and paint it white while we're still painting and at we have to keep painting over their paint cause we want the wall to be blue not white. If they didn't do any reset people would get their blue wall done and leave, since there's nothing to do anymore
I may be stupid but I was under the impression that this is already how Battlegrounds ratings worked...
i think before the external and internal mmr ratings were the same - but now since they're doing seasonal resets, they are no longer going to be.
There's no reason to complain about it. Rating can be a very upset thing; anyone that play chess can tell you that. The peoples reach 1200, 1500, 1800 elo points and stay there for the rest of the life; the truth is that the elo rating system really can measure your skill so after you get in your high score you cant climb anymore, that can be really bad in game: you dont wanna play 1, 2 or 3 months and dont see any progress.
So that is why now we get a fake MMR rating. So you can think that you can get better: just need play more (that, of course, is not 100% true).
But in the other hand the Elo System is good because you never will fight with someone much more strong than you (that makes fell bad in games too). So blizzard wanna keep something like that in the game. That is why we got the 'invisible rating'.
If you disagree show me any option that can solve these two problems:
- You want fair fights (you dont wish one fight where someone has more than 1/8 chance of winning before even the start)
- You wish that the players get some sense of progression. Nobody wish to stay in the same rating for the next 10 years (even if reality says that will happen when you get in your peak).
Dude I'd rather hit that wall and try to break it than hit the wall and then be magically sent 100 meters from the wall and having to run back to the wall in order to try and break it, just to be sent back to point 0 again and again whenever I hit the wall.
The changes are so people don't just hit the wall and go "I'm ok with that result" and never play again, and so people don't go "I don't want to play this anymore, I'm worth at least 14K and I'm stuck at 6K cause it's rigged".
It's not really for the experience, it's to keep people playing for as long as possible, which is fine, but don't mask it for them.
I'm sick of hidden internal ratings. Your external rating should be your only rating. It has severely diminished my enjoyment in Ladder to be facing tier 1 decks from the first day of a month at Bronze 10. It will do the same to any "rating reset" in battlegrounds.
Exactly!!
The hidden mmr in Ranked mode is a shit. Here comes another one in battlegrounds.
I hate this "hidden MMR" thing.
It makes rating in BG or rank in ladder mean literally nothing. And the only true indicator of skill is hidden.
Very bad. Another attempt increase playing time artificially. I can't play often, but I'm at decent 11k and was slowly climbing and having fun. Now everyone, who just play much, will get insta 6000 floor, no matter how bad they are, and I will spend half time just to catch them up, and probably will give it up.
So basically, your external rating is useless and just there to look pretty?
My main question is, they will give rewards for this pre-season?
Does this mean rating/MMR is finally visible to everyone? If so, this is so nice! We will no longer need to keep asking our friends how high their rating is and we will know the rating of our opponents too!
Yes, i think this is a great add to the game too.
No, you get it wrong. Your rating/MMR will be now hidden for everybody, including you. All you will see is some points, and more you play, more points you get, and basically can't loose them up to some level.
No...the MMR was shown until now and now it's no longer visible.