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Evolution of chess: Popularity of openings over time

randalolson.com

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Re: Evolution of chess: Popularity of openings over time

#21

Post by adamconroy »

rhiever wrote: post #20
adamconroy wrote: post #17

The analysis is interesting. However I'm not sure it has much practical value due to transpositions. For example, as white I play 1.Nf3 and if black plays d5 I play d4 and we have a d4 opening. If black plays c5 I play c4 and depending on what black does it will transpose into either an English opening (1. c4) or a maroczy sicilian (1. e4) or an indian defence (1. d4). So basically, my opening move would be classed a…

If any of the alternative paths were common enough, they would show up in the charts as well. I didn't limit the analysis to a particular set of moves; I simply counted all of the paths present in the data set and showed the most common ones. This is why two variations of the Indian Defence show up in the "White's second move" chart. I think it'd be interesting to try to combine all possible paths for an opening into…

It is quite complicated. The examples I gave are quite simple, but in a lot of cases the transpositions can happen many moves into the game. The maroczy sicilian example I referred to is one of these cases, where I might not actually play e4 until say move 8-10, but in a general sense it probably should be classified as an e4 opening.

As an overall guide I think what you have done is fine, but I suspect something in the order of 10-20% of games might be subject to transpositions where the opening move isn't an accurate categorization.

Re: Evolution of chess: Popularity of openings over time

#22

Post by Cogito »

The visualisation I would most like to see with respect to openings is a 'heat map' like diagram, showing how likely a given piece is to occupy each square after n moves.

Are there any squares never used after the first move?

Just what weight is given to the centre of the board after the first few moves?

This sort of information could be communicated really well with a view of the board, and the pieces expected to be in each square.

Re: Evolution of chess: Popularity of openings over time

#23

Post by bane »

ThrustVectoring wrote: post #14
bane wrote: post #11

Out of curiosity, is chess solvable yet by computers? Meaning, is it possible to simply brute force every possible legal game up to n moves and determine all the winning and losing move sets? What's this number look like theoretically? (I'm sure in the general sense games with a very large n aren't as I suppose a game could be played in perpetuity)

>every possible legal game up to n moves That's easily above 10^30 positions. 10^30 is a very low lower bound, too. So, uh, no .

Well, that's why I specified n moves. Entire games can take 2 moves. So for n=2, it's probably pretty easily solvable. Probably for n=3 and maybe 4 as well.

It's also not strictly exponential as n increases, pieces are removed from the board for example restricting the number of legal moves as the game progresses.

There's probably interesting solvable subsets up to large numbers of n, like maximum captures as the game progresses, or all games where there are zero captures or some such.

It's not a simple matter of calculating every possible theoretical legal or non-legal state of the board with all the pieces.

Re: Evolution of chess: Popularity of openings over time

#24

Post by dfan »

rhiever wrote: post #20
adamconroy wrote: post #17

The analysis is interesting. However I'm not sure it has much practical value due to transpositions. For example, as white I play 1.Nf3 and if black plays d5 I play d4 and we have a d4 opening. If black plays c5 I play c4 and depending on what black does it will transpose into either an English opening (1. c4) or a maroczy sicilian (1. e4) or an indian defence (1. d4). So basically, my opening move would be classed a…

If any of the alternative paths were common enough, they would show up in the charts as well. I didn't limit the analysis to a particular set of moves; I simply counted all of the paths present in the data set and showed the most common ones. This is why two variations of the Indian Defence show up in the "White's second move" chart. I think it'd be interesting to try to combine all possible paths for an opening into…

The traditional way to handle this is by classifying a game according to the last cataloged position that occurs in it. This is how ECO classification works; you can see its catalog of positions at http://www.chessgames.com/chessecohelp.html.

For example, just after White plays 1.Nf3, the game is classified as A04, but after 1...d5 2.d4, it's now officially a D02, over in the Queen's Pawn category, just as it would have been if the game had started 1.d4 d5 2.Nf3.

Databases usually keep track of chess openings played by ECO code rather than by specific moves, exactly so that these transpositions are handled smoothly.

Re: Evolution of chess: Popularity of openings over time

#25

Post by szierk »

fgp wrote: post #19
bane wrote: post #11

Out of curiosity, is chess solvable yet by computers? Meaning, is it possible to simply brute force every possible legal game up to n moves and determine all the winning and losing move sets? What's this number look like theoretically? (I'm sure in the general sense games with a very large n aren't as I suppose a game could be played in perpetuity)

AFAIK, the most complex board game solved to date is checkers http://en.wikipedia.org/wiki/Chinook_(draughts_player) . Chess is also solvable, but researchers are far from solving it yet

An important distinction here is that checkers is also only weakly solved (Connect Four, by contrast, is strongly solved). https://en.wikipedia.org/wiki/Solved_game

This means that Chinook can play perfectly from the start position against any set of opposing moves, but if you play a move on Chinook's side that it wouldn't play for itself, the resulting position is probably not solved by Chinook.

An arbitrary position is in fact very unlikely to have been solved.

Re: Evolution of chess: Popularity of openings over time

#26

Post by pbhjpbhj »

bane wrote: post #23
ThrustVectoring wrote: post #14

Earlier quoted context omitted.

>every possible legal game up to n moves That's easily above 10^30 positions. 10^30 is a very low lower bound, too. So, uh, no .

Well, that's why I specified n moves. Entire games can take 2 moves. So for n=2, it's probably pretty easily solvable. Probably for n=3 and maybe 4 as well. It's also not strictly exponential as n increases, pieces are removed from the board for example restricting the number of legal moves as the game progresses. There's probably interesting solvable subsets up to large numbers of n, like maximum captures as the gam…

>as n increases, pieces are removed from the board for example restricting the number of legal moves //

As the pawns are moved to make way for the back row the number of legal moves increases very quickly. For example if white plays d2-d3 then it frees the King, Queen and Bishop to move; 2 possible moves are removed and 8 are added.

Re: Evolution of chess: Popularity of openings over time

#27

Post by rhiever »

dfan wrote: post #24
rhiever wrote: post #20

Earlier quoted context omitted.

If any of the alternative paths were common enough, they would show up in the charts as well. I didn't limit the analysis to a particular set of moves; I simply counted all of the paths present in the data set and showed the most common ones. This is why two variations of the Indian Defence show up in the "White's second move" chart. I think it'd be interesting to try to combine all possible paths for an opening into…

The traditional way to handle this is by classifying a game according to the last cataloged position that occurs in it. This is how ECO classification works; you can see its catalog of positions at http://www.chessgames.com/chessecohelp.html . For example, just after White plays 1.Nf3, the game is classified as A04, but after 1...d5 2.d4, it's now officially a D02, over in the Queen's Pawn category, just as it would…

I wish I knew about this earlier! Thanks for explaining it to me though. :-)

Re: Evolution of chess: Popularity of openings over time

#28

Post by TylerE »

Blahah wrote: post #12
rhiever wrote: post #9

Earlier quoted context omitted.

I double-checked my data set to look into this, and you're right. Nearly all of the Pircs in that time period were done by a guy named Moheschunder Bannerjee: https://en.wikipedia.org/wiki/Moheschunder_Bannerjee He contributed to the development of the Indian Defence.

Why do you all have your own datasets of historical chess moves? Is this a popular playground for data analysis, or is it something chess learners study?

Chess compresses very well. You can fit pretty much every meaningful game ever played into 10gb or so.

Re: Evolution of chess: Popularity of openings over time

#29

Post by toolslive »

rhiever wrote: post #20
adamconroy wrote: post #17

The analysis is interesting. However I'm not sure it has much practical value due to transpositions. For example, as white I play 1.Nf3 and if black plays d5 I play d4 and we have a d4 opening. If black plays c5 I play c4 and depending on what black does it will transpose into either an English opening (1. c4) or a maroczy sicilian (1. e4) or an indian defence (1. d4). So basically, my opening move would be classed a…

If any of the alternative paths were common enough, they would show up in the charts as well. I didn't limit the analysis to a particular set of moves; I simply counted all of the paths present in the data set and showed the most common ones. This is why two variations of the Indian Defence show up in the "White's second move" chart. I think it'd be interesting to try to combine all possible paths for an opening into…

for some openings, the 'paths' do not really matter. You might have 25 transpositions leading up to the same position after 10 moves. A well known example is the classic isolated d4 pawn position that might come from: - Nimzo Indian - Caro-Kann Panov - QGD - Slav - c3 Sicilian - Alekhine's defence and others.

Popularity has not a lot to do with the openings themselves but with other things like a good book being published, or a popular match (like WC).

Another thing you have is that some variations are really popular, and have good results, but are at one point refuted by a single game. As a result of this, the variation dies. but remains to have very good statistics.

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