4

What is the expected performance gain of adding Transposition Tables and then MTD(f) to pure alpha beta pruning for chess?

In my pure alpha beta pruning I use the following move ordering:

  • principal variation (from previous iterative deepening iteration)
  • best move from transposition table (if there is any)
  • captures: highest captured then lowest capturing
  • killer moves
  • history heuristics

With above setup I get following average results for depth 9:

  • pure alpha beta: X nodes visited
  • alpha beta+TT: 0.5*X nodes visited
  • MTDF(f): 0.25*X nodes visited

I expected better results and I wanted to make sure if that's as good as it can get or if there is something wrong with my implementation?

I search with accuracy of 0.1 pawn.

PanJanek
  • 6,593
  • 2
  • 34
  • 41

0 Answers0