Don, how do I make 10,000 positions thingie? Could you post a Win x64 executable of this? I browsed the threads and found only bigsimilat.kit which seems indeed big compared to similar.kit, but I don't know what to do with it. With 2,000 positions the standard deviation of the results seems like 1.5%, which is way too large. The whole span of little similar to very similar engines is about 7%, 3% error margins 95% confidence may distort heavily the results.Don wrote:I actually have a version with 10,000 positions. I recently removed almost 2000 of them due to the fact that EVERY engine played the same move (out of 18 engines I tested)Laskos wrote: Houdini 1.51 is a pure copy of Houdini 1.5, I put it to set the upper boundary of these pretty non-deterministic engines. My problem is mostly statistical, 10,000 or so positions are needed at least, and in no case the claim about cloning could be made more than circumstantially. More like a property of some engines.
I agree with you about the circumstantial evidence. The only thing this test can show you is how much stylistic similarity there is between two programs.
In fact, I think the test tells you mostly about the evaluation function of the two programs, and hardly anything about any other part of the program. However it's my belief that this is the most important and difficult part of a chess program and what separates the men from the boys.
The second issue, some engines (quite a few) refuse to perform the test correctly, either halting or giving some outlandishly low results (like 12%).
Kai

