I have seen learning AI put into Rock Paper Scissors games which enable the decision of the next item to show based upon the previous options the user has selected.
I.e. the game will have a history of moves made and will know that 60% of the time a user will follow Rock, rock with paper.
obviously this is a far easier option than a game of chess.
however taking this concept to a game of chess, not only would you need to consider the current state of the board, but also the opponents style of play