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Subject: Re: DTS article robert hyatt - revealing his bad math

Author: Vincent Diepeveen

Date: 11:22:05 09/03/02

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On September 03, 2002 at 13:51:52, Uri Blass wrote:

It is about the second digit being round, because
that makes the chance you have such a speedup 1/10 of
a chance.

Bob claims a 2.0 speedup which bob claims according to
his paper based upon counting up all times then dividing
by total times.

However if we look at every speedup individually then
if you get a 2.0 speedup that's in a range of 1.95-2.04
RIGHT?

Please answer that question.

A speedup of 2.0 lies in a range of about 1.95-2.04

So i hope you realize that chance it is 2.00 is exactly 1/10
of a chance.

How big is the chance that 50 numbers in a row have
a speedup in parallel search of 2.00 then?

How big is the chance that all numbers end at a 0?

We talk about a lot of data. about 24 positions in the
article times 1,2,4,8,16 processors.

The 16 processor times and nodes i believe. i didn't
statisticaly analyze very well whether he has lied
about the number of nodes as well. This is not important
in my feeling.

My feeling says he didn't lie about the number of nodes.
He had however very bad speeedup 1..8 processor, so he
had to modify them *all* in order to look good.

No one checks search outputs in computerchess. the
peer reviewers are a joke with regard to the DATA you present.

Yes they know a lot about how to write an article, but they
know nothing from how to present DATA. In fact they
take everything for granted.

I can however imagine in this case that most peer reviewers
didn't statistically analyze the search times. If you divide
the 1 processor search time by the 2,4,8 times you will
clearly see that all these search times are a big fraud
however.

If every number has 1/10 of a chance to get there, then
we talk about a very *small* chance Bob had this data by
accident. 0.00000000000000000000000000000000000000001

>On September 03, 2002 at 13:45:09, Vincent Diepeveen wrote:
>
>>On September 03, 2002 at 13:31:15, Uri Blass wrote:
>>
>>there is 24 positions x 1,2,4,8,16 processors.
>>so there is pretty much data. You can see it in
>>first icca from 1997 where bob describes DTS.
>>
>>If i claim an average speedup of 1.90 then there is
>>a domain of about 1.85 - 1.949 where the speedups
>>fall in. However bob's speedups all fall in only
>>1/10 of it. So for every rounded number there is a
>>1/10 chance.
>>
>>A few numbers where they have .01 that's a round off
>>error usually. He modified his data a little but not
>>enough to get outside the error margin of statistical
>>analysis on data.
>>
>>In short for every round number there is about a 1/10 chance
>>to happen.
>>
>>1/10^(24*3.5) is about 1 / 10^30
>
>I did not read the article but
>I saw in your post only one round number with a lot of 0's
>(13).
>
>I understood from your post that 13 is only relevant to
>position number 10
>
>Here is the data again:
>
>pos   2      4      8   16
>1  2.0000 3.40   6.50   9.09
>2  2.00   3.60   6.50  10.39
>3  2.0000 3.70   7.01  13.69
>4  2.0000 3.90   6.61  11.09
>5  2.0000 3.6000 6.51   8.98876
>6  2.0000 3.70   6.40   9.50000
>7  1.90   3.60   6.91  10.096
>8  2.000  3.700  7.00  10.6985
>9  2.0000 3.60   6.20   9.8994975 = 9.90
>10 2.000  3.80   7.300 13.000000000000000
>
>Uri



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