Handicaps

As far as I know, there were no changes made to the ranking system recently, it is still the same ranking system and it still gives handicaps as it should.

What is probably the source of the misunderstanding is the fact that there is a whole another rating system below the kyu/dan numbers you see. Those kyu/dan number you see are rounded numbers for the benefit of humans (because they are easily readable), but for the math purposes there is a set of another points (called Glicko) below these numbers - those are used for calculating the handicaps (because they are more precise).

The number of HC stones depends on those more detailed points. Therefore it can sometimes seem to differ by a stone because of the rounding.

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Thank you, but how do you explain that one minute when playing with a 18k I was given 3 handicaps stones - I was 21k so one stone by rank. Then the next minute I was 20k and someone a 17k requested to play with me but I was not given any handicaps?

and now I just had a game with a 16k and I was given the handicaps… 3 of them. With a 17k none Hmmm something is wrong here!

Besides calculating your rank, the rating system estimates how precise it knows your rank. If it isn’t sure enough about your or your opponents rank, it doesn’t give the full handicap.

In https://online-go.com/game/21777305, the rating system wasn’t sure about your opponents rating, so it reduced it to 1.

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What do you mean "reduced it to 1? The system as you saw gave me 0 zero. I dont understand how that is reduced to 1? Sorry, I dont understand.

I think there is something important for you to understand.

Komi counts for 1 handicap.

The system didn’t give you “zero”, it took away white’s komi, which is worth 1 stone.

If you don’t accept that this is how it works, you will find it even harder to understand.

Handicap system:

Equal rank: 6.5 komi
1 kyu difference: 0.5 komi
2 kyu difference: 0.5 komi + 1 stone
3 kyu difference: 0.5 komi + 2 stone

etc

You can’t calculate the rank difference by using the APPROXIMATE rank that you see next to your name.

Thats because someone who shows as 17k might be “almost 16k”. Like they are 16.1k

And somone who is 16k might be “only just” 16k. Like they are 16.0k.

These two people are only 0.1k different. They are treated as equal for handicap, even though it is 17k vs 16k.

HTH

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The rank displayed next to a player’s name might not exactly be the rank used to calculate handicap.

I went to find an older post where I explained this, but it turns out it was in a previous thread also started by @Interestinggame

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In my previous post, I was asserting that it is not.

Testing confirmed this, as I tried to explain - sorry if the explanation fell flat :S

@Eugene, my choice of phrasing “might not exactly be” is not meant to cast doubt on your assertion of “that it is not”, which I do agree with. I meant to express something along the lines of “might not be reflective of the actual ratings used”. I use the word “might”, since in some cases, by chance of rounding, the difference between the displayed ranks will in fact correspond to the handicap stones assigned. For example, if the players actual ranks are 3.0k and 5.9k, that gets displayed as 3k and 6k, and 3 handicap stones are assigned.

I understood your explanation, but I thought it left out a crucial factor, namely the effect of deviation, which appears to also be playing a role here in further impacting the handicap assigned.

In the post that I linked, I try to further explain how deviation might impact things (which is a phenomenon that seems to be confirmed by @flovo and @anoek earlier in that thread), since in that thread, there was a case where a game between a 22k and 18k resulted in only 1 handicap, whereas even the worst case (floor) rounding would still seem to dictate that there should at least be 3 handicap.

The rounding effect that you discuss in your previous post would only explain apparent handicap discrepancies of up to 1 stone. However, the person that started this thread specifically complained about a larger apparent discrepancy here: Handicaps

Note that @flovo alluded to the effect of deviation earlier (here: Handicaps), but I thought it would be helpful to further elaborate on how and why rating deviation could impact handicap, since the poster immediately expressed further confusion in response here: Handicaps

However, when I went to look for my old post that explains this, I also discovered that it was in a thread that was also started by the same user that started this thread. Hence, it seems that we are largely addressing the same questions in both threads to the same person again.

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Ah - now I understand what you meant by “might” :smiley:

FWIW, it was the word “be” that got me.

If you had said “match” I would have understood :slight_smile:

I haven’t thought about the maths and probability etc, but instinct tells me that between a quarter and half the time it won’t be what you expect if you just look at the published rank.

And I too was surprised to learn that deviation/uncertainty also plays a role! :open_mouth:

But it makes sense when you think about it :slight_smile:

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This is confusing me slightly, doesn’t it normally go

  • komi 6.5 - no handicap
  • komi 0.5 - (one stone)
  • komi 0.5 - two stones
  • komi 0.5 - three stones
    Etc

The +1 stone is confusing me. Is it saying one extra stone than before or? I can’t follow it. As in the way it appears isn’t the number of stones on the board in say Japanese rules right?

Anywho I’m not sure if the confusion of the op is the ogs implementation only or also the numbers of stones generally but in the case of the latter, pictures are handy :slight_smile:

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It’s the number of additional stones black gets. Since black plays first, you get the number of black stones by adding 1 to these numbers.

A 1 stone handicap is in fact a no Komi handicap, since the number of black stones don’t change. The table above trys to incorporate this fact by counting the additional stones only.

The table on the Wikipedia page is the same, but formulated differently.

https://en.m.wikipedia.org/wiki/Handicap_(go)#Handicap_placement

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Right flovo has it.

I just want to paraphrase and emphasise that the way we Go players talk about this is totally confusing.

This is because originally handicap was not linked to komi at all.

Originally a “1 stone handicap” was the same as “1 kyu difference” and it really was one stone.

Now we have a stupid shorthand for a “1 kyu difference” we say it is “1 stone of handicap”.

But the implementation is that you don’t get a stone, you just get komi removed :woman_facepalming:

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From the point of view of japanese/korean rules games, it doesn’t feel like black plays first when there’s additional handicap stones, since they have default placements. White makes the first free placement.

For me personally it’s less confusing to just say how many stones you actually get on the board instead of +x stones, which really translates to x+1 on the board, and I’d prefer to say 0.5 komi is still komi considering there are rulesets with 0 komi.

Anyway, it was just on the off chance that was part of the confusion.

Actually, it translates to x-1 on the board. Confused yet? :smiley:

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Yes

I think this is how we talk:

“I will give you a 1 stone handicap, because we are 1 stone apart in rank, because I am 17k and you are 18k.”

X=1.

Number of stones on board = X-1 = 0.

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Hmm, but when saying “I will give you two stones” do you not actually mean “put two stones on the board”?

If someone told me they’d give me 5 stones, I would assume I get 5 star point stones starting. I always understood that komi is reduced for all handicap games as a given, not that it should count as a stone in any sense. Then just treat one stone as an exception since I’ll give you one stone sounds more like, I’ll let you play first, which black does normally.

For instance in books on handicap go, if you look up a 5 stone game, how many stones do you imagine are on the board at the start for black? :slight_smile:

Eg Kageyamas book on handicap go

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In a 5 stone game black plays 5 stones and after that white plays the first stone.

In a 1 stone game black plays 1 stone and after that white plays the first stone. Which you could also describe as: Black begins. No difference to a normal game at all in this respect. (So removing komi is what really happens in a 1 stone game.)

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This is true, but I don’t think it helps.

In a 0 stone (no handicap) game black plays 1 stone and after that white plays the first stone. Which you could also describe as: Black begins.

See? You can’t escape from the fact that the difference between a zero stone game and 1 stone game is not one stone on the board.

It’s just stupid terminology, plain and simple. The cause of it is that not so long ago there was not such thing as komi, and one stone handicap really did mean one stone.

Then komi was introduced, and somehow it was seen as a suitable replacement for 1 stone.

Personally I don’t understand why the rulemakers chose to use komi as one stone. I can’t really see why the advantage that black has over white is “one stone worth”.

After all the years of experience it took to come up with the number 6.5 as the right amount of komi, isn’t it a bit too convenient that it happens to equal one stone? I doesn’t ring true to me - it just seems like someone saw a convenience and it became law (not that I have any idea how it happened - it just seems that way).

As black, would you give your white opponent a stone in exchange for komi?

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