Speedchase, I see what you're saying about moves that are right according to current go theory, but might be suboptimal. Still, I think that one in three is quite high. Some considerations:

Pros play near perfectly in the late endgame.
Just as with our games, there will be long sequences of forced moves. If you pick the wrong joseki, it may be that only one move is wrong--the rest are the best choice you can make given the wrong move.
Pros certainly play quite well in capturing races and tsumego.

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Occupy Babel!

I think that this comment hits the point pretty accurately. People are referencing pro commentary on their games, which is cool, but isn't necessarily indicative of everything that is "bad" or "wrong" in one's game. A pro may comment only on things that he thinks need improvement for the given player's level. He might think, "Well, this guy is 1k, and a 1k should know this. He needs to know that this move is bad." There could be even moves that a pro would say are "good" in your game, because they are good for your level. But he might not play the same move in the same situation, because at the pro level it may be a bad move.

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be immersed

Evidence?



In principle everybody can.

I acknowledge what you are saying, but I can't agree with Robert's opinion.

Yes, a review might not be the best way to find this number because many things are left unsaid. And indeed, some moves might be good on our level but yet clearly suboptimal on theirs.

However, I can't agree with Robert because the definition of bad was left quite clear. Would a pro play this given move? Does he consider it an option or would he call it a mistake if it was another pro playing it? Even better, would a pro study group call this move a mistake, stating that there are options clearly better?

I'm not sure that this part was mentioned earlier. I think that it makes the field for "bad" moves much wider than some other interpretations.

Namely, when a pro does a review for a kyu player, I'm pretty sure he doesn't often review pointing out pro-level mistakes.

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be immersed

I thought that while combinatorial game theorists (for instance) are able to come up with places where professionals miss the right play, it is not altogether easy or common. Moreover, many of those errors may be single stone errors, followed by the best play given the initial error.

This doesn't hurt my point. I wasn't making a comparative point, just commenting on the number of professional mistakes we might see.

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Occupy Babel!

Would a pro play this given move?

The poll clearly says how many of your moves would a pro classify as bad. Let's take the classification that HKA's pro teacher used - bad, slack, good & great. There are degrees of bad and good moves. If you say that the definition of bad is asking would a pro play this then HKA's slack moves would be defined as bad and probably a number of his good moves. Likely, a pro would play so many different moves than we would that it would make the distinction of a truly bad move meaningless.

It is not easy because proving correct endgame can be difficult!

It is not common because only scarcely a few theorists make research on played games.



May or may not...

No. In your new post, cited below, you have increased clarity.



This is still pretty ambiguous though. The more a pro or a pro study group or an amateur or an amateur study group studies a move the more likely it is recognised as mistake.

I saw bad to mean G-d would not play this move if he was randomly moved to this position in the game, of anything other than perfect play. That's why I put my number so high.

If our defintion of a bad move becomes anything other than perfect play, then the discussion becomes pointless as we don't know what perfect play is or what God would do.

On this point, reading over the few pro game commentaries I have, I think pros often won't play a move because it's too calm. That is, there's nothing wrong with the move, but pros like to make the game less straightforward and encourage complications (it makes for more exciting games, which is good when you make your living by playing games).

That is, at the pro level, "good" and "bad" aren't really concerns. A pro can make most stones work for him one way or another, so there aren't many properly bad moves in a game. Rather, it's about more metagame concerns like taking control of the flow of the game.

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1k KGS

Well, it depends on how "good" is defined. With the updated definition by the OP, whether another pro would play a move is an indicator as to whether it is good or bad. So if a pro takes metagame into account for move selection, the definition of a "good" move should as well.

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be immersed

We don't know how many moves that we play, a pro would also play, so by that argument the discussion is already pointless and I am just making pointless in a different way.

Exactly. That was my part of my point in my first post above. We don't know what move any one pro would play. However, as evidenced by HKA's post, we can hear from those with a pro teacher as to how many moves were classified as bad, as opposed to how many were slack, good or great. It would be interesting to see an average number of bad and slack moves, defined as those classified by a pro, for each rank. Of course, the data would be very subjective, depending on what pro and how polite they were being, but it would still be interesting nonetheless.

Let me try to shed some light here. For me, there is no doubt that my "slack" moves are bad. Often, during the review, the move is played and the simple question is asked "anything better?" Often slack is a very good describer, sometimes it is a timing issue. But in the pro world, the move is bad. Also, it should be pointed out, that while the games often reach the endgame, they rarely are completly completed.

In my declining former 5 dan world these moves are acceptable, but need improvement. Let me present better definitions.

Let me be clear, I know my teacher very well, since 1986. I know what he means - he would never say much and certainly not all of the below, but this is absolutely what he means:

Great - Wow, this is a really good move, not joseki, did not think you knew this or did not think you would come up with it, might have even caught me off guard - great job.

Good - This is essential, a must move, a pivotol point. You may or may not have been expected to get it - but you did and you need to know how important it was.

No Comment - These moves are fine, and I know you know this so no need to comment.

Slack or "Anything Better" Not an optimal move. You are addressing an issue, but not well and certainly not in the best way. Perhaps correct locally but missing the plot. At a pro level, a bad move.

Bad - Hello, is the tv on? Are you a kyu player? Can you explain to me why I waste two hours with you every two weeks? Oh thats right, you pay me.

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My days of not taking you seriously are certainly coming to a middle

I think it would be more useful to count bad ideas instead of bad moves. A bad idea might show up as one bad move. It might also show up as a sequence of moves that is self-consistent and locally good, but the wrong direction; or an attempted tsumego sequence that doesn't work. Does that make the whole sequence bad moves? To me it is just one bad idea. Or, say there is one urgent point lurking on the board which is overlooked, resulting in failing to play there at several non-consecutive chances. How many bad moves would that count as?

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Main Entry: zing·er Pronunciation: \ˈziŋ-ər\
1 : something causing or meant to cause interest, surprise, or shock
2 : a pointed witty remark or retort

I put that 'all my moves' would be considered 'bad' by a pro. Not because I think that my play is horrid, just because I don't think enough about my moves. I play, especially when stressed, based on instinct and feel, and I know a pro would consider this to be the worst idea ever. So, even if a pro would make a move I made, he certainly would do so with more thought and care than the rediculous 'Eh. That looks complex. Let's do that.' which informs most of my moves. So, it's more that I think I'm not playing go, than that a pro might not choose to play stones on the same grid points I do.

I remembered this thread the other day while reading a commentary. So I thought it would be interesting to tally the "bad" plays in a pro game with a good commentary for comparison to our efforts. I was reading an 1856 game between Honinbo Shuwa and Murase Yakichi (the future Honinbo Shuho). This game was presented as the February 2009 famous game supplement to Igo Magazine in Japan. The little shirt-pocket-size supplements routinely present some of the best analysis of games that I have seen in Japanese.

This particular game is interesting because it was played between teacher (8p) and pupil (then 5p) but was no quick knock off. GoGoD gives the date of the game as 1856-08-29. However, Igo has a much more detailed account of the playing of the game. It began on 1856-07-29 and continued on 07-30, 08-02, 08-04, 09-10, 10-13, and 10-16 at three different venues. The pro giving the commentary was Fukui Masaaki (9p) but much of the commentary itself is based on an older analysis by Kitani Minoru and Go Seigen. So both the game and the various analyses are reasonable examples of "high-level" works.

I ignored all comments regarding changes in fuseki theory and joseki practice. These we will not take as "bad" plays in the context/era of the game. Only where one of the commentators clearly questioned a play as bad and offered a better alternative did I count it, e.g. 'Black 13 was an overplay'. On this basis eleven moves in the game were considered bad: 13, 27, 84, 99, 100, 119, 127, 147, 153, 176, and 191. Within these eleven two are weaker. Go Seigen gives an alternative to 27 but Fukui writes that in fact play is likely to revert to the actual game. Black's 119 is noted as probably an overplay but no clear alternative line is given. In addition, 30 may be considered a bad play although the commentary says that probably White felt it was sufficient. Many other plays are looked at in considerable detail without finding better plays for either side. This is pretty amazing since from 13 to 84 the game is one big fight finally stretching across the entire bottom of the board.

Anyway I have added the comments regarding the bad plays to the game record in GoGoD and posted it below; it is game 1856-08-29a for those who have it in hand. Enjoy!

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Dave Sigaty
"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21

In part it depends upon what you mean by perfect play. It is not at all unusual for a pro to choose an inferior play in the endgame that does not end up costing the game, or costing a point.

In part it depends upon time limits. In the late 19th century top level pros played nearly flawless endgames, in the sense of not giving up a point. In the early 20th century, after the introduction of time limits, top level pros rarely gave up a point with plays that gained less than 3 points. With today's quick time limits, even top level pros give up points to perfect play fairly late in the game.

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The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.