an American computer scientist, AI-researcher and entrepreneur, Ph.D. from Stanford University in 1991 on automatic abstraction in planning . Along with Richard Korf, he elaborated on a Unified Theory of Heuristic Evaluation functions and Its Applications to Learning on optimization of feature weights by hill climbing methods and linear regression. In one experiment, a set of relative weights for different chess pieces was automatically learned.
Experiments with Chess
Excerpt from A Unified Theory of Heuristic Evaluation functions and Its Applications to Learning. :
As a serious test, we chose the game of chess and a simple evaluation function consisting only of material advantage. The experiment was to see if the learning program would approximate the classically accepted weights for the pieces: 9 for the queen, 5 for the rook, 3 for the bishop, 3 for the knight, and 1 for the pawn.
The chess program was implemented using a two-ply mini-max search with alpha-beta pruning and quiescence. 1400 half moves were made between each regression. If neither side won during a game it was stopped after 100 half-moves and a new game was started. For purposes of the experiment, a win was assigned one more than the total initial material value, and the individual piece values were rounded off to the nearest 0.5. The pieces stabilized at: Queen, 8.0; rook, 4.0; bishop, 4.0; knight, 3.0; pawn 2.0. ...
- Jens Christensen, Richard Korf (1986). A Unified Theory of Heuristic Evaluation functions and Its Applications to Learning. AAAI-86, pdf
- Jens Christensen (1986). Learning Static Evaluation Functions by Linear Regression. in Tom Mitchell, Jaime Carbonell, Ryszard Michalski (1986). Machine Learning: A Guide to Current Research. The Kluwer International Series in Engineering and Computer Science, Vol. 12
- Jens Christensen (1990). A Hierarchical Planner that Generates Its Own Hierarchies. AAAI-90, pdf
- Jens Christensen, Adam Grove (1991). A Formal Model Classical Planning. IJCAI 91, pdf
- Jens Christensen (1991). Automatic Abstraction in Planning. Ph.D. thesis, Stanford University, pdf
- Jens Christensen | LinkedIn
- Jens Christensen: The Innovation Interview | Brulte & Company, September 8, 2014