We are installing the Gull engine for some chess enthusiasts in an organization. We would like to set 6 difficulty levels from beginner to master using depth. Is there someone who can advice us about which values are the most accurate and progressive for each level?
-
Can you just do 3,4,5,6,7,8 etc?– SmallChessCommented Jun 28, 2016 at 7:26
-
depth is the number of half moves the search nominally looks ahead, so it's a little bit hard to define. Middle game junior usually gets 14-16 depth to be competitive– Siberian ScoutCommented Jun 28, 2016 at 8:14
1 Answer
You may find this post by the developers of the website https://lichess.org/ helpful.
Although they use Stockfish as the engine, they set the search depths as such (note that they have eight levels of play):
- AI level 1: skill 3/20, depth 1, 50ms
- AI level 2: skill 6/20, depth 2, 100ms
- AI level 3: skill 9/20, depth 3, 150ms
- AI level 4: skill 11/20, depth 4, 200ms
- AI level 5: skill 14/20, depth 6, 250ms
- AI level 6: skill 17/20, depth 8, 300ms
- AI level 7: skill 20/20, depth 10, 350ms
- AI level 8: skill 20/20, depth 12, 400ms
I have personally played and seen others play against the varying levels. Level 1 is almost joke worthy--the computer may move his queen completely into danger, completely miss checkmates, etc.
On the other hand, level eight is crushing; beating it requires repeated practice over the same line (at least, that is the only way I've seen people beat it).