Please precisely define...

[Bill Spight]

Although, in the strict sense, it depends on defining "local", there are (in my new book) pretty good criteria of conditions when playing elsewhere is attractive. Conditions such as this: "The set of local groups is stable."

Now, I propagate that the player chooses(!) what to consider as groups or belonging to a set of local groups. Hence locality can be derived from those given groups. Well, in principle. In practice one also needs some convention of how to form a local enviroment around a known, given group. E.g., the group plus all its liberties and maybe plus further (empty) intersections "in between". We get a locale. Playing outside the locale is then considered a tenuki.

(Everything needs to be updated every move.)

This is the sort of thing I was hoping for... except I think this may be computationally infeasible for my purposes. I'm not even sure there's a known solution for determining the set of local groups.

There is a paper about the possible omission number of a group (i. e., how many times you can tenuki), with an algorithm to determine the number, based upon the judgement of a Japanese amateur 6 dan. OC, you have to be able to say what a group is before you can determine its PON. I'll look it up.

...
Like sente and gote, tenuki depends on the concept of locality. Towards the end of the game, it is possible to define independent regions of the board (except for ko fights, OC), and then tenuki is clear. Early on, however, regions of the board are seldom completely independent. Then what is considered tenuki is fuzzy. If a play is tactically related to the last play, it is not tenuki, no matter how far away it is on the board. If it is not tactically related, it is tenuki, no matter how close it is.

This is a great definition for a human, but "tactically unrelated" is not easy to translate into an algorithm.

Well, it is possible to program fuzziness. (Not that I have ever done it, but I have a couple of books. ) The problem there is that you need to get somebody's judgement about what is tenuki. (Your own is fine for your purposes, I am sure. But involving humans takes time.)

Perhaps I should have said a bit more originally on what I'm trying to do-- I potentially need to answer this question several hundred times per move per pro game, in all 65,000+ pro games of GoGoD. I only build my database occasionally, so it doesn't have to be super fast, but it does need to complete in my lifetime. So, basically I'm hoping for a definition that could be applied with reasonably accurate results by a 35kyu...

I think that your own judgement, coupled with a joseki book, would be good enough for that.

Alright, well, I'm not sure what I'll end up doing, but a related question: I have considered giving an "urgency" rating to each position, which would be basically "when this position appears in pro games, how many moves on average pass before the players play locally again? So 0.0 would indicate that pros always play locally immediately, and larger numbers indicate less urgent positions (pros play N moves elsewhere before coming back to this position). Does this seem like an worthwhile metric?

Thanks for the input

That sounds a lot like the PON. Which is a better metric, perhaps, than how long before play returns to the locale, since the latter depends upon the whole board.

[jts]

Question: can't you just call a move that shows up fewer than X times in the database a tenuki?

This has the disadvantage that occasionally when a move on the other side of the board shows up in a well-known fuseki, DJ will test us on the whole-board sequence rather than the corner sequence; and that some more obscure variations of the more obscure joseki will be lost; but on the whole, that's not a huge problem, right?

[Bill Spight]

BTW, the concept of joseki is not set in stone. Apparently joseki that cover more than a single corner are being developed now. But that is not a new thing. Here is an ancient joseki. Is there a tenuki?



Edit: I have not really studied the book, but I do not think that it uses the term, tenuki. Often it seems like plays like are intended as tenuki, but. . . .

[perceval]

Just to explain this real quick: the marked stones suddenly appear because in all 8 games where black played (the bad shape) 9, those stones were already on the board.

So i think this is a good illustartion of my proposal:
if several games have the same "tenuki" sequence then its proably not a tenuki .. because the common thing thsoe game have in common is the joseki at hand. (thisis true where you are a bit later in the game but this is where the issue arise anyway : early on divinfg the board in 4 quandrats is enough)
here the marked sequence is played in the 8 games between 7 and 9 and is part of joseki: you have more info if you aggreagate data from sevral games

Not sure it works often though

[Bill Spight]

Here is a reference to the PON paper:

Estimating the Possible Omission Number for Groups in Go by the Number of n-th Dame
by: Morihiko Tajima, Noriaki Sanechika

COMPUTERS AND GAMES
Lecture Notes in Computer Science, 1999, Volume 1558/1999, 265-281, DOI: 10.1007/3-540-48957-6_18

Springer charges for a download, but maybe you can contact one of the authors. You might also check on the computer go mailing list.

[Bill Spight]

Tenuki means to play somewhere else.

Not really. The Japanese is a noun not a verb. The verb usage is te wo nuku or tenuki suru.

I think that English grammar allows the use of tenuki as a verb or a noun. As in, "if it's only worth 15 points, tenuki".

The point is (under the Japanese definition), it occurs when you do not respond to a threatening move just played by the opponent. Playing ine one area and ending in sente then playing somewhere else is not a tenuki. There is a sense of bravado in a tenuki, as in the proverb "if it's only worth 15 points, tenuki" (or variations on the number).

An important point. If Black plays on the 3-4 in an open corner and White plays in another corner, that is not tenuki.

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Likewise, for Black to play somewhere else after is not tenuki.

However, the threat can be very weak.

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For to tenuki would be bad, I think, but for to tenuki is not uncommon. The cut is not such a strong threat. Bravado overstates the case, I think.

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Likewise, in this case tenuki is normal. Black's threatened attack is not severe.

I think that in general amateurs do not tenuki enough. And I think that the reason has less to do with caution or bravado than with tunnel vision.

[John Fairbairn]

Bill, I'm not convinced that your last two examples would normally be described as tenuki in Japanese, though of course they could be. The point is, here, you are not so much ignoring the opponent's last move (as you say the threat is weak) but rather deferring your response while you make a probe elsewhere. Although it doesn't always happen, I think you have a strong intent of returning soon in cases like the above, and so are not really ignoring the opponent. I do think the key nuance tends to be "ignore". Japanese has other ways of saying "play elsewhere" when "ignoring" does not apply (e.g. hoka ni tenjiru), and these appear often in go texts.

For Daniel's purpose, the message I take from that is that "tenuki = ignoring a threat" is not really a common joseki concept. When an otherwise common move is not played, it is usually deferral. If so, Daniel's idea of counting how long a move is deferred seems to be absolutely on the right track. And, while being careful not to overtax my brain, I'm not sure deferral in joseki has much to do with locales or the price of fish either. Which justifies his idea even more.

[RobertJasiek]

your book, is it available in the US?)

It needs to be ordered from Europe. E.g., from me postage is EUR 3.45.

but I want to actually measure things

I think my symbolic levels work as a measurement, if your application is simply to determine whether to tenuki at all or which of two very different plays elsewhere is more urgent. Similar levels are not distinguished because I think that other considerations (of other concepts, terms) would have to be taken into account then.

(I would be very surprised if you have a procedure such that a 30 kyu could come up with the same "unrest level" that you would for a given position).

I think if we say 18 kyu, then the the chance is reasonable that he and I would find the same level, once the reader has made himself familiar with the concepts stability, urgency, investment.

I'm not sure what all is involved in your "unrest level"

One must be able to notice that a group is unsettled, that a local sente play is available, which major development directions there are from a group, whether a group is important or can be sacrificed etc. Since you want to do it by a program (I think), it must be able to cut its tactical reading by noticing that something is (rather) quiet or stable.

Then you get a few conditions like "add 2 to the level for each weak, unsettled, important group".

how well does it model pro play?

I have not done statistics because (besides lack of time) many other decisions can play a role. (E.g., when basically one would tenuki, one could still consider playing preliminary sente forcing moves.)

[RobertJasiek]

There is a paper about the possible omission number of a group (i. e., how many times you can tenuki), with an algorithm to determine the number, based upon the judgement of a Japanese amateur 6 dan.

Now this is very related to my book's terms n-connected and p-alive, which define exactly that, see
http://senseis.xmp.net/?NConnection

OC, you have to be able to say what a group is before you can determine its PON.

No. One simply chooses some stones / strings as a group! (Only if you want to do that particularly meaningfully would you want to acquire some greater ability for the selection.:)
)

I have a couple of books.

What do they say about tactical relation and the like?

[Bill Spight]

I have a couple of books.

What do they say about tactical relation and the like?

They are about fuzzy logic and programming.

[lightvector]

There seems to be a disconnect between Daniel's problem and the proposed suggestions.

The metric needs to be very simple, to be possible to implement as an practical algorithm and applied by computer on the order of 100 million times. It is already difficult to program any sort of open-space tactical reading with concepts and goals such as stability, connection, etc. Gnugo is probably the best freely available attempt at this sort of thing (that is, hardcoding expert knowledge and judgement), and we all know how poor Gnugo is. Then on top of all that, getting it fast enough...

And with millions of positions, it is not feasible to do it all manually in any reasonable amount of time.

The approach perceval and Daniel mentioned he is using right now is pretty close to what I would try first, if I were trying to implement this. I don't see an obvious way to do much better, besides fiddling and tweaking the algorithm and inspecting the results to see where it goes wrong, to try to fix it.

As for averaging number of moves before playing again, I think it's a metric worth investigating. I don't know how well it will do, but I'd go ahead and implement it and look at some of the results to see if they give anything reasonable. Even though it does depend on the rest of the board, averaged over thousands of games, there's a good chance it will correlate with some notion of urgency.

You might also consider different ways of weighting the number of moves before another local play prior to averaging. For instance, the difference between "played immediately" to "played after 5 moves" might matter a lot more than the difference between "played after 45 moves" to "played after 50 moves".

[RobertJasiek]

I do not share the pessimism about programs and expert knowledge. If you can't implement tactics, then let the tactics be done by Monte Carlo and the like. It can't be that tough to describe as code things like stable, urgent, investment, unsettled, important (too important to be sacrificed) along the definitions for those terms in my book. Note that, unlike traditional expert system programs, we do not run into their difficulty of mutually competitive expert level terms because I invent them essentially hierarchically and the OP is interested only in tenuki considered alone.