Bill, I sat in on a presentation today by one of the creators of Minigo, a deep learning go program that is based on the AlphaGo Zero paper. As a logo for Minigo, the creators chose a picture of a smiling robot happily falling off a tall ladder. The reason for this choice is that while Minigo can play strong games of go, it occasionally gets suckered into chasing a long ladder that results in a loss. For those who don't know, a ladder in the game of go is a series of moves that repeat and propagate across the board, as each side tries to outrun the other: https://en.wikipedia.org/wiki/Ladder_(Go) To correctly predict the outcome of continuing a ladder, each player must look many moves ahead and thus it's a "deep position" similar to the chess positions you mentioned. Although deep, ladders are simple linear sequences with no branching and thus humans quickly learn how to predict the outcome. After seeing the presentation, I read the original AlphaGo Zero paper and found this (*emphasis* mine): *"*AlphaGo Zero rapidly progressed from entirely random moves towards a sophisticated understanding of Go concepts including fuseki (opening), tesuji (tactics), life-and-death, ko (repeated board situations), yose (endgame), capturing races, sente (initiative), shape, influence and territory, all discovered from first principles.* Surprisingly, shicho (“ladder” capture sequences that may span the whole board) – one of the first elements of Go knowledge learned by humans – were only understood by AlphaGo Zero much later in training. * " This supports the argument that the AlphaGo Zero algorithm is weak at deep positions, particularly when they haven't been thoroughly explored by the algorithm previously. ---Gary On Mon, Jul 16, 2018 at 10:53 AM Gary Snethen <gsnethen@gmail.com> wrote:
I think Alpha Zero would fare poorly in these situations unless it trained on them directly.
The current deep learning algorithms are good at emulating intuition and perception, but aren't good at deep analysis and executive planning, which is what's required for board positions like these.
---Gary
On Mon, Jul 16, 2018 at 2:41 AM Bill Gosper <billgosper@gmail.com> wrote:
Does anybody know how Alpha Zero would fare on RKG's endgame composition in https://en.wikipedia.org/wiki/Richard_K._Guy ? Put another way, how would RKG's intended solution fare against Alpha Zero? Similarly, can Alpha Zero win those computer-generated "hundred move rule" positions?
https://www.chess.com/forum/view/fun-with-chess/longest-mate-official---mate... --rwg
-- Sent from my iPhone