Hi,

short description of the test:

I have finished the next test. Matador had to search all 300 positions with pure alpha-beta algo with zero window, quiescence search and nullmove (R=2). The results are more than depressing! Can the nullmove effective work without sorting of moves? At the moment I only know, my nullmove does work with sorting. What do you think?last week I started to research the effect of isolated improvements

of my program (Matador) on the playing strength of the program.

At first I compiled a version of Matador without any improvements.

This version worked without any kind of sorting, extensions, pruning,

hash … The evalution based exclusively on material.

The results of pure alpha-beta algo:

//Test: wacnew.epd / Time: 5s

total solve time : 952.17 s / solved: 115/300

avrg. depth: 5.5 / avrg. max depth: 21.6

avrg. QS: 77.8% / avrg. MO: 61.7%

Okay, these are the results of the test with nullmove:

//Test: wacnew.epd / Time: 5s

total solve time : 940.21 s / solved: 120/300

avrg. depth: 5.9 / avrg. max depth: 21.7

avrg. QS: 80.8% / avrg. MO: 59.8%

From my point of view the small increase of the average depth (without quiescence search) is very remarkable. I have expected an increase of 2-3 plys and some tests with sorting of moves confirmed the expectation.

Probably the expense of the nullmove without sorting is equal the use!? Perhaps someone can check it too?

At next I will research the effect of my search extensions on the playing strength of Matador.

In the past I used the following extensions:

1 ply – OneReplayExtensions

1 ply – CheckExtensions

1/4 ply – 2 or more checks in a line

1/4 ply – Check by other piece (not by the moved piece)

1/4 ply – Check by two pieces

1 ply – PassedPawnExtensions

1/2 ply – RecaptureExtensions

I am afraid, some of these extensions are nearly worthless.

Best regards,

Stefan