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Subject: Re: cute position

Author: Uri Blass

Date: 08:03:33 08/15/03

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On August 15, 2003 at 10:52:04, Anthony Cozzie wrote:

>On August 15, 2003 at 10:38:47, Uri Blass wrote:
>
>>On August 15, 2003 at 10:27:44, Anthony Cozzie wrote:
>>
>>>On August 15, 2003 at 10:13:05, Uri Blass wrote:
>>>
>>>>On August 15, 2003 at 10:03:06, Anthony Cozzie wrote:
>>>>
>>>>>On August 15, 2003 at 09:56:35, Uri Blass wrote:
>>>>>
>>>>>>On August 15, 2003 at 08:36:00, Anthony Cozzie wrote:
>>>>>>
>>>>>>>[D]r4r1k/1b3p1p/pq3N1p/n3p2N/Pp6/3Bn3/1PP1Q1PP/R4R1K w - - 0 26
>>>>>>>
>>>>>>>1. Rg1 Rfc8 2. Bxh7 Qd4 3. Rab1
>>>>>>> = (-0.89)      Depth: 5/12     00:00:00.25     40kN
>>>>>>>1. Rg1 Rfd8 2. Rae1 Bxg2 3. Rxg2 Nxg2 4. Qxg2 Qg1 5. Rxg1
>>>>>>> = (-1.00)      Depth: 6/16     00:00:00.70     153kN
>>>>>>>1. Rg1 Rfd8 2. Rae1 Bxg2 3. Rxg2 Nxg2 4. Qxg2 Qb7 5. Rxe5 Qxg2
>>>>>>> + (-0.70)      Depth: 7/19     00:00:01.36     377kN
>>>>>>>1. Rg1 e4 2. Bxe4 Bxe4 3. Nxe4 f5 4. Nef6 Rfd8
>>>>>>> = (-0.09)      Depth: 7/19     00:00:02.15     685kN
>>>>>>>1. Rg1 e4 2. Bxe4 Bxe4 3. Nxe4 f5 4. Qxe3 Qxe3
>>>>>>> = (0.00)       Depth: 8/23     00:00:03.48     1192kN
>>>>>>>1. Rf2 e4 2. Bxe4 Bxe4 3. Nxe4 f5 4. Nef6 Rfc8 5. Qd3 Rd8
>>>>>>> = (-0.04)      Depth: 9/30     00:00:20.53     7692kN
>>>>>>>1. Rf3 Bxf3 2. Qxf3 Qd4 3. Re1 Qh4 4. g3 Nxc2
>>>>>>> = (0.25)       Depth: 10/33    00:00:42.98     16634kN
>>>>>>>1. Rg1 Qd4 2. Rae1 Nec4 3. Bxc4 Nxc4 4. Rd1 Qc5 5. Nd7 Nb6 6. Nxf8 Rxf8
>>>>>>> = (0.43)       Depth: 11/39    00:01:25.00     33717kN
>>>>>>>1. Rf3 Bxf3 2. Qxf3 Qd4 3. Re1 Qh4 4. g3 Nac4 5. gxh4 Ng4 6. Bxc4 Nf2
>>>>>>> + (0.73)       Depth: 12/48    00:05:37.18     133815kN
>>>>>>>1. Rf3 Nxg2 2. Qxg2 Rg8 3. Qe2 Rg5 4. Be4 Rc8 5. h4 Rg6 6. Nd7 Qd4 7. Bxb7 Qxh4
>>>>>>>8. Qh2 Qxh2 9. Kxh2
>>>>>>> = (1.24)       Depth: 12/48    00:12:16.28     298098kN
>>>>>>>
>>>>>>>Very tough for Zappa.  5 minutes.  It changes its mind a lot here as well, which
>>>>>>>never helps - Rg1, then Rf2, then Rf3, then Rg1, then Rf3 again.
>>>>>>>
>>>>>>>anthony
>>>>>>
>>>>>>I wonder how does zappa knows not to consider first Rg1 at depth 12.
>>>>>>zappa has a score for Rg1 at depth 11 and the first output at depth 12 is a
>>>>>>score for Rf3.
>>>>>>
>>>>>>Uri
>>>>>
>>>>>I'm not sure what is strange (other than the slow times): Zappa likes Rg1 at
>>>>>depth 11, fails high on Rf3 at depth 12, and ends up with Rf3 as the best move
>>>>>at depth 12.
>>>>>
>>>>>anthony
>>>>
>>>>The fact that I see no score for Rg1 at depth 12.
>>>>Does zappa have a score for Rg1 at depth 12 before finding Rf3?
>>>>
>>>>If it has a score then I do not see it in the output and if it decides to search
>>>>Rf3 before Rg1 at depth 12 then how does it know to do it.
>>>>
>>>>Uri
>>>
>>>Zappa only prints the PV at the end of the search - no intermediate pvs.
>>>
>>>anthony
>>
>>In this case I have 2 questions:
>>1)how can you know the time that it needs to find a move?
>>2)why does it print 2 pvs for Rf3 at depth 12 and 2 pvs for Rg1 at depth 7?
>>
>>Uri
>
>Zappa uses an aspiration window.  The first character shows how the search went:
>- -> window failed low, + -> window failed high, = -> good.  So Zappa tried
>PVS(p, 0.5) and failed high. Then it tried PVS(p, 1.25) and was successful.  In
>other words, Zappa doesn't treat the root position differently.
>
>I'm not sure I'm doing a very good job of explaining this.

If I understand correctly zappa finished iteration about the moves
and got during that iteration a score for Rg1 that was not published and a fail
high for Rf3 that finished the iteration.

After doing it it did the iteration again at the same depth and got an exact
score for Rf3.

5:37.18 is the time to find Rf3 because of the fail high but 1:25 is not the
time to find score for Rg1 but the time to finish iteration 11 that is not the
same.

Uri



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