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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #381 Posted: Wed Jun 13, 2018 7:33 am 
Tengen

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Javaness2 wrote:
Is the number where entry rating essentially equals exit rating? If so are you iterating the calculation over all players?

Yes. No. (and just using current ratings not at start/end/middle of event so those could have changed a bit). Plus the Thai 4d he lost to might be a bit stronger than 2400, he also beat the UK's Daniel 4-5d and a Dutch 5d. In fact I think I played him in Thailand a year or two ago when he was 2-3d; I beat him but as he was young and it was clear he had a great desire to win I'm not surprised he's improved.

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #382 Posted: Wed Jun 13, 2018 7:37 am 
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Uberdude wrote:
Javaness2 wrote:
Is the number where entry rating essentially equals exit rating? If so are you iterating the calculation over all players?

Yes. No. (and just using current ratings not at start/end/middle of event so those could have changed a bit). Plus the Thai 4d he lost to might be a bit stronger than 2400, he also beat the UK's Daniel 4-5d and a Dutch 5d. In fact I think I played him in Thailand a year or two ago when he was 2-3d; I beat him but as he was young and it was clear he had a great desire to win I'm not surprised he's improved.


My immediate concern would be can it be valid if you answer Yes.No. ?
Wouldn't you do better to have a script that would essentially submit, then resubmit(with updated initial ratings) results 3 times?

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #383 Posted: Wed Jun 13, 2018 7:39 am 
Judan

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Bojanic wrote:
As promissed earlier, here is analysis I made on middle game moves of Carlo Metta in four games - two internet games that preliminary analysis of deviations histogram showed that were very similar to Leela, and two of his live games from WAGC.
Attachment:
Metta analysis Bojanic.pdf


{snip}

In my opinion, thing is simple - if we have a player who is playing online like Leela, and playing much weaker in live games, then he was using Leela for online games.
No need for complicated statistics, or guessing why he plays much better online.


Thank you very much for your hard work and analysis. I will take a look at the PDF file, at least. :)

But I disagree with your last paragraphs. I won't go into detail, since that's what this whole discussion has been about. But if you are using those criteria, you do need statistics to evaluate the data.

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #384 Posted: Wed Jun 13, 2018 8:06 am 
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theoldway wrote:
But you involuntarily used the statistics everywhere in your work, with the aggravating circumstance of having taken very few samples chosen a priori among those already more similar to Leela.

Are you familiar with the term cherry-picking?

https://en.wikipedia.org/wiki/Cherry_picking

You took the games most similar to Leela, among these games you took a dozen of moves among those more similar to Leela, and guess what? they are similar to Leela! utterly unexpected :lol: :lol: :lol:

?

Since you have not obviously read what I previously wrote and posted, here is entire research procedure again:
- in preliminary research I analyzed all games from A league. Deviations histograms were analyzed, and ones with least deviations from Leela were selected for detailed analysis
- since plays in opening and endgame could be very similar to Leela's play, I decided to analyze middle game only. Those parts of the game also deviate little from the Leela, but can easily show false positive results, since joseki sequences could be learned, engame could be forced or with little variations.
- middle game was analyzed in two aspects: middle game tenukis, and sequence of moves during play
- middle game play in those two games was compared to play in two of the live games (all available recent live games).

Therefore, it is not just handful of moves, it is entire middle game in two online and two live games.

Regarding other live games of Carlo Metta, please note that some of them were played after objection that he used Leela, therefore it would be less likely that he might use Leela again in same manner (entire game), or if at all.

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #385 Posted: Wed Jun 13, 2018 8:15 am 
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Bill Spight wrote:
Thank you very much for your hard work and analysis. I will take a look at the PDF file, at least. :)

But I disagree with your last paragraphs. I won't go into detail, since that's what this whole discussion has been about. But if you are using those criteria, you do need statistics to evaluate the data.

In that case please take a look at XLS file in the additional data.
In it, you have Metta's moves in 4 games, compared to Leela's suggestions for those moves.
Actually, here is screenshot of it:
Attachment:
Screen Shot 2018-06-13 at 5.10.00 PM.png
Screen Shot 2018-06-13 at 5.10.00 PM.png [ 134.29 KiB | Viewed 352 times ]


I have also noted which A moves were forced.


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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #386 Posted: Wed Jun 13, 2018 8:31 am 
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Bojanic wrote:

Therefore, it is not just handful of moves, it is entire middle game in two online and two live games.

Regarding other live games of Carlo Metta, please note that some of them were played after objection that he used Leela, therefore it would be less likely that he might use Leela again in same manner (entire game), or if at all.


Chess players needed years and more than 200,000 games of thousands of players to develop, test and estabilish an anti-cheating protocol. You took a bunch of online games of one player (not randomly, but those you've observed as similar to Leela) and 3 live games played from 7 to 12 months later than the online games.

Are we supposed to take you seriously?

Please take your seat in the Salem witch trial, you deserve it. :clap:


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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #387 Posted: Wed Jun 13, 2018 8:42 am 
Judan

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Bojanic wrote:
As promissed earlier, here is analysis I made on middle game moves of Carlo Metta in four games - two internet games that preliminary analysis of deviations histogram showed that were very similar to Leela, and two of his live games from WAGC.
Attachment:
Metta analysis Bojanic.pdf



I confess that I had hoped to see a go analysis of the games, not Leela output histograms. I was glad to see that you had picked out important tenukis. But I was surprised that you only looked at Metta's plays. We really need to compare the variations in his play with the variations in others' plays. Also, output by other programs, such as Zen or LeelaZero/Elf would be good for comparison.

You have discovered an important piece of evidence, Leela's top choice which is a blunder, but which Metta played. To have an amateur player who is playing well make a blunder is not all that unusual, but when that blunder is also the choice of a super strong program, that is unusual. One thing we would like to know is how often Leela makes similar blunders. Here is also where the choices of other strong programs, such as Zen, Golaxy, or Leela/Efi could be helpful to know. If they also choose that blunder, then the fact that Metta did too is not so significant. It would be a blunder that is easy to make, even if you are playing well. The choices of other strong amateurs would also be relevant, by the same token.

Bojanic wrote:
maf wrote:
Also, if I did not miscount, all games together yield only about 30 or so data points (tenuki moves). That is not a lot, it can suffer from sheer coincidence. If you're only 99% certain (which is a lot from so few data), then that practically ensures that each year, several honest players would be 'convicted' of cheating. You need to have at least 5 or 6 nines. It's not simple.


So you mean that if player uses Leela for 1-2 games, he cannot be punished, because of too little nodes?


Depending upon how he uses Leela, probably not, if the evidence is only statistical. There won't be enough data. The fact that the original verdict was based upon the statistics of only one game was a big red flag for me.

Edit: As Regan points out, without physical or behavioral evidence, cheating is very difficult to prove.

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Last edited by Bill Spight on Wed Jun 13, 2018 8:55 am, edited 3 times in total.
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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #388 Posted: Wed Jun 13, 2018 8:44 am 
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theoldway,

I see that you have registered especially for this topic, and that you want to show that proving online cheating is impossible.
OK, that is certainly your right, but it has to be noted on topic.

Since in your messages are mostly accusations and attacks on me, without much analysis, I would ask you to introduce yourself for further discussion.
I am registered here by my name, here is my EGD card.
http://www.europeangodatabase.eu/EGD/Pl ... y=10337085


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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #389 Posted: Wed Jun 13, 2018 8:54 am 
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Bill Spight wrote:
But I was surprised that you only looked at Metta's plays. We really need to compare the variations in his play with the variations in others' plays. Also, output by other programs, such as Zen or LeelaZero/Elf would be good for comparison.

I have looked other's player moves also, you can see them in RSGF files.
They are much more different than Leela's, lot of moves outside suggestions, etc.

And why do we need to analyze other players?
Analysis should be made on play of one player in live and in internet games.

Bill Spight wrote:
You have discovered an important piece of evidence, Leela's top choice which is a blunder, but which Metta played. To have an amateur player who is playing well make a blunder is not all that unusual, but when that blunder is also the choice of a super strong program, that is unusual.

In other games of Metta I analyzed, there were life&death moves that were better than Leela's.
IE against Stankovic cut was not in the suggestions, in other game he connected his group on the left side on the first line.
So he can play L&D problems better than Leela.

Bill Spight wrote:
One thing we would like to know is how often Leela makes similar blunders.

It did make it this game, and as I mentioned previously, failed to see some moves in other games.

Bill Spight wrote:
Here is also where the choices of other strong programs, such as Zen, Golaxy, or Leela/Efi could be helpful to know. If they also choose that blunder, then the fact that Metta did too is not so significant. It would be a blunder that is easy to make, even if you are playing well. The choices of other strong amateurs would also be relevant, by the same token.

For those two games, it is very clear that he showed very large similarities to Leela's play, why would you analyze it with other programs?
It could make sense in other games where it is not similar to Leela.

Bojanic wrote:
Depending upon how he uses Leela, probably not, if the evidence is only statistical. There won't be enough data.

If that is the case, we can conclude that any online official games are pointless, since it is impossible to prevent cheating.


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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #390 Posted: Wed Jun 13, 2018 9:06 am 
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Bojanic wrote:
Bill Spight wrote:
But I was surprised that you only looked at Metta's plays. We really need to compare the variations in his play with the variations in others' plays. Also, output by other programs, such as Zen or LeelaZero/Elf would be good for comparison.

I have looked other's player moves also, you can see them in RSGF files.
They are much more different than Leela's, lot of moves outside suggestions, etc.

And why do we need to analyze other players?
Analysis should be made on play of one player in live and in internet games.

{snip}

Bill Spight wrote:
Here is also where the choices of other strong programs, such as Zen, Golaxy, or Leela/Efi could be helpful to know. If they also choose that blunder, then the fact that Metta did too is not so significant. It would be a blunder that is easy to make, even if you are playing well. The choices of other strong amateurs would also be relevant, by the same token.

For those two games, it is very clear that he showed very large similarities to Leela's play, why would you analyze it with other programs?

(Emphasis mine.)

The short answer to making comparisons with other players and other program is this: It's the differences that make a difference.

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #391 Posted: Wed Jun 13, 2018 10:19 am 
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Bill Spight wrote:

One thing we would like to know is how often Leela makes similar blunders. Here is also where the choices of other strong programs, such as Zen, Golaxy, or Leela/Efi could be helpful to know. If they also choose that blunder, then the fact that Metta did too is not so significant. It would be a blunder that is easy to make, even if you are playing well. The choices of other strong amateurs would also be relevant, by the same token.



It seems that also Zen 7 and Leela Zero make this blunder. Maybe it's not that easy to spot as real game tsumego. It's kind of tricky.


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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #392 Posted: Wed Jun 13, 2018 12:19 pm 
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theoldway wrote:
Bojanic wrote:

Therefore, it is not just handful of moves, it is entire middle game in two online and two live games.

Regarding other live games of Carlo Metta, please note that some of them were played after objection that he used Leela, therefore it would be less likely that he might use Leela again in same manner (entire game), or if at all.


Chess players needed years and more than 200,000 games of thousands of players to develop, test and estabilish an anti-cheating protocol. You took a bunch of online games of one player (not randomly, but those you've observed as similar to Leela) and 3 live games played from 7 to 12 months later than the online games.

Are we supposed to take you seriously?

Please take your seat in the Salem witch trial, you deserve it. :clap:


I find your post inappropriate and ungrateful to people who are trying to make real sense of this situation. Your attitude strengtheners my opinion that Carlo's and anybody else's online games are completely meaningless and that trying to analyse and prove cheating one way or another is not going to lead to any satisfactory results.

Someone analyses games and proves beyond reasonable doubt that cheating has occurred. This is met by protest and derision. A debate ensues. Since there is no admission of guilt, there is no real result. The whole exercise has been a waste of time.

Given this situation I can not see how Pandanet can continue hosting online tournaments, at least tournaments that anyone takes seriously. I am sure they have better things to do with their time than to run around after cheaters and get stuck in disputes once cheating is discovered. They have nothing to gain.

I find this comment: "Regarding other live games of Carlo Metta, please note that some of them were played after objection that he used Leela, therefore it would be less likely that he might use Leela again in same manner (entire game), or if at all." interesting. How is he supposed to "use Leela again" in a live game?

Finally, I find it fascinating that anyone embroiled in this kind of controversy would find it appropriate to be chief referee for a major go tournament, regardless of guilt or innocence.

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #393 Posted: Wed Jun 13, 2018 12:40 pm 
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Gobang,
My obvious lapsus.
I menat online games, pgetc after round 4.

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #394 Posted: Wed Jun 13, 2018 12:43 pm 
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Gobang wrote:
Someone analyses games and proves beyond reasonable doubt that cheating has occurred. This is met by protest and derision. A debate ensues. Since there is no admission of guilt, there is no real result. The whole exercise has been a waste of time.


I'm sorry, but I didn't see here a proof that cheating occured beyond reasonable doubt.

And my opinion on this matter is that it's probably impossible to prove it beyond reasonnable doubt in this case.

Gobang wrote:
Finally, I find it fascinating that anyone embroiled in this kind of controversy would find it appropriate to be chief referee for a major go tournament, regardless of guilt or innocence.


But I can agree to this, he should step down from this position. And as you say, that's regardless of guilt or innocence.


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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #395 Posted: Wed Jun 13, 2018 12:56 pm 
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Tryss wrote:
I'm sorry, but I didn't see here a proof that cheating occured beyond reasonable doubt.


No need to be sorry. It is your opinion and you have every right to it. "Reasonable doubt" will always be subjective.

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Post #396 Posted: Wed Jun 13, 2018 1:34 pm 
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theoldway wrote:
Bill Spight wrote:
One thing we would like to know is how often Leela makes similar blunders. Here is also where the choices of other strong programs, such as Zen, Golaxy, or Leela/Efi could be helpful to know. If they also choose that blunder, then the fact that Metta did too is not so significant. It would be a blunder that is easy to make, even if you are playing well. The choices of other strong amateurs would also be relevant, by the same token.


It seems that also Zen 7 and Leela Zero make this blunder. Maybe it's not that easy to spot as real game tsumego. It's kind of tricky.


Assuming you mean the Metta-Ruzicka game, that's what I posted about. LeelaElf makes the same oversight, as did Frank Jansen 6d in a very similar shape in another game. Btw, I think it's better to call this an oversight (of not seeing the black cutting move killing through shortage of liberties) than a blunder, as to me a blunder implies a very bad move where a good one was available, but here the situation is white is dead (or a desperate ko connection out depending on the outside) and there is no good move. The mistake/blunder is allowing yourself to get into this shape earlier.

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #397 Posted: Wed Jun 13, 2018 5:01 pm 
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Gobang wrote:
theoldway wrote:
Bojanic wrote:

Therefore, it is not just handful of moves, it is entire middle game in two online and two live games.

Regarding other live games of Carlo Metta, please note that some of them were played after objection that he used Leela, therefore it would be less likely that he might use Leela again in same manner (entire game), or if at all.


Chess players needed years and more than 200,000 games of thousands of players to develop, test and estabilish an anti-cheating protocol. You took a bunch of online games of one player (not randomly, but those you've observed as similar to Leela) and 3 live games played from 7 to 12 months later than the online games.

Are we supposed to take you seriously?

Please take your seat in the Salem witch trial, you deserve it. :clap:


I find your post inappropriate and ungrateful to people who are trying to make real sense of this situation.

I agree. Bojanic has conducted a careful and important investigation. Whatever his errors, he deserves our respect and gratitude. :)

Quote:
Your attitude strengtheners my opinion that Carlo's and anybody else's online games are completely meaningless and that trying to analyse and prove cheating one way or another is not going to lead to any satisfactory results.


Analyzing a few games statistically is unlikely to lead to any definitive results. As theoldway indicates, it took a lot of data to develop and test an appropriate statistical methodology for detecting cheating at chess. For go we are just getting started on that task.

Quote:
Someone analyses games and proves beyond reasonable doubt that cheating has occurred. This is met by protest and derision. A debate ensues. Since there is no admission of guilt, there is no real result. The whole exercise has been a waste of time.


Gobang wrote:
"Reasonable doubt" will always be subjective.


I sense your frustration. But the journey of 1,000 miles begins with a single step.

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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #398 Posted: Wed Jun 13, 2018 9:45 pm 
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Gobang wrote:
I find it fascinating that anyone embroiled in this kind of controversy would find it appropriate to be chief referee for a major go tournament, regardless of guilt or innocence.


Suppose innocence and the referee's honest impartiality, that is, if he thinks to be partial when meant to act or decide, assume he temporarily retreats from his duty with respect to a task during which partiality has an impact.

A referee has the right to be a referee. As a referee, he deserves respect as a referee. A referee has the right to be, or have been, involved in a dispute on his own because he, as a player, has the same rights to justice as those players he judges on. He just must maintain impartiality, i.e., if the case he judges on is significantly related to the case he is, or has been, judged on, he must temporarily retreat to dissolve the particular conflict of partiality.

(There are exceptions, such as in the German Championships, where the appeals committee members necessarily belong to the players so every such referee is necessarily partial. Christoph Gerlach set the precedent that, in this tournament, this kind of partiality is allowed because each possible substitute referee is also necessarily partial because the other players' results also affect his own tournament results relative to the other players. For practical reasons, there are no extra persons forming the appeals committee.)

Let me repeat: As a referee, he deserves respect as a referee. Do not cast unjust doubts on his integrity as a referee. As a referee, he deserves this respect not to be loaded with unjust doubts. What applies to a referee also applies to a chief referee, member of an appeals committee or member of the EGF Rules (etc.) Commission (third instance, although I do not know whether Panda tournaments are EGF tournaments and subject to it).

A player involved in a dispute has the right to question impartiality of his referee(s). In that case, the referee(s) must honestly and sincerely consider whether / inhowfar they are indeed impartial. If they find (and explain) their impartiality, then the player must respect them to judge on his case. (See also the precedent EGF Rules Committee judging about Zeijst - Dinerstein: a questioned impartiality was considered, rejected and explained.)


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 Post subject: Re: “Decision: case of using computer assistance in League A
Post #399 Posted: Thu Jun 14, 2018 1:00 am 
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A few observations on Bojanic's analysis. For the game Carlo Metta – Reem Ben David, he analyzed middle game tenuki moves 51, 59, 65, 87, 97, 101.

  • I still have Champion Go 1.1.4 on my smartphone. This program is quite weak compared to Leela or to the two players, probably at most 5k EGF. Among these 6 moves, it found move 65, so we can assume that Carlo Metta could easily find move 65 by himself.
  • If we want to make Bojanic's method more scientific, we should give a precise definition of tenuki that a computer could check. I don't know if this has already been done, but in any case I am not able at the moment to provide such a definition.
  • Let's call a "non obvious move" a tenuki move played between moves 50 and 150 (or maybe 30 and 180) and which is not suggested by a weak program (could be GnuGo or another program).
  • Find at least 100 random online games played before the existence of strong AI, with sufficiently long time settings (no blitz), and with both players being mid-dan. For each of these games, determine the number of "non obvious moves", and how many of these are Leela's suggestions.
  • From these data, estimate how likely it was for Carlo Metta to have such a high degree of similarity a) for the match Metta-Reem b) for this match and all his preceding PGETC. If the likelihood is very small, like 1:1000000 or even 1:100000, this will be a very strong indication of cheating although not a hard proof. If not, the case should be dismissed.
  • More important than solving this particular case is to design a scientific method to prevent future cheating. We don't know for sure if cheating has already occurred in online or OTB tournaments, but we know that cheating will occur in the future. Cheating discovered by statistical methods can justify at least that a match be replayed and monitored, while someone found guilty of using a hidden electronic device should be banned from tournaments for several years.
  • There are very few cases where just statistical methods (without material proofs) could be enough, for instance when a player improves very quickly, beats several dan players at a tournament but is unable to solve 15 kyu tsumegos or tesujis.
  • In online tournaments, if matches are not monitored or recorded by webcams, it will always be possible to cheat in a subtle way, like using a strong software just once or twice during the game. This will be undetected by statistical methods, just like when athletes are injected just enough EPO/growth hormone/testosterone/whatever so that their blood or urine analysis looks normal; these athletes should be considered innocent until material proof is found.


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Post #400 Posted: Thu Jun 14, 2018 1:31 am 
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Especially in unsettled positions, there is more than one possible definition of local versus elsewhere. One possible definition is:

An empty intersection is _local_ to a two-eye-alive string if the opponent cannot prevent the player from both becoming part of one two-eye-formation of his.

Note that such a definition does not define local to an uncapturable seki string. Also note that local to one particular two-eye-alive string is not the same as local to an unequivocal group of a player's two-eye-alive strings. For definitions of 'prevent', 'two-eye-alive' and 'two-eye-formation', see my webpage.

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