Question Regarding Move Ordering

[StackFish5]

Hello there, I have some inquiries regarding move ordering. Currently, I have MVV-LVA move ordering, move ordering based on the piece square tables, killer moves, and the history table. The hash move system has not been implemented but I still want to include it in my question. The question that I have is how would these methods be ranked in priority? For example, would MVV_LVA be more significant in determining the priority of a move being searched than killer moves? Thank you in advance for the advice.

[KhepriChess]

There's a lot that can be found about move order on this forum (and through the chess programming wiki on this topic).

But I believe, in general, it goes:

1. Hash move
2. Captures
3. Killer moves
4. History moves

Not all captures need to necessarily be sorted all in #2. Bad/losing captures can be sorted after killer moves or after history moves, but whether that works depends on your engine. For me, sorting bad captures after killer moves didn't work until I had late move pruning (which coincidentally I've just been testing today).

[alvinypeng]

Strong engines usually do something like this:

1. Play hash move
2. Generate captures and score them based on capture history and/or MVV-LVA. Capture history is usually much more important than MVV-LVA
3. Loop through captures from best to worst score. If a capture is a "good" capture (has a positive SEE), play it
4. Killer moves
5. Generate quiet moves and score them based on quiet history
6. Play quiet moves in best-to-worst score order. Just make sure not to play the hash move or killer moves twice
7. Play remaining "bad" captures

[lithander]

2. Generate captures and score them based on capture history and/or MVV-LVA. Capture history is usually much more important than MVV-LVA

I have never heard about Capture history before. Can you elaborate?

[alvinypeng]

2. Generate captures and score them based on capture history and/or MVV-LVA. Capture history is usually much more important than MVV-LVA

I have never heard about Capture history before. Can you elaborate?

Capture history is history heuristic for captures. Quiet history is indexed by something like [piece][to], whereas capture history is indexed by something like [piece][to][captured piece type].