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Subject: Re: Deeper Gary has just been released

Author: KarinsDad

Date: 20:39:44 03/03/99

Go up one level in this thread


On March 03, 1999 at 17:15:26, Don Dailey wrote:

>On March 03, 1999 at 14:30:44, KarinsDad wrote:
>
>>On March 03, 1999 at 12:40:05, Don Dailey wrote:
>>
>>[snip]
>>>
>>>I'm tired of speculating however.  The truth of the matter is
>>>that Deep Blue won.  The only scientifically valid conclusion
>>>you can draw from this is that it is slightly more likely that
>>>Deep Blue is the better match player.
>>
>>Actually, this conclusion is just as speculative as a conclusion in the other
>>direction.
>
>Woops, a little mistake by you,  better review your theory.

Ok, I will.

>
>If you do an ELO rating of the match  you will discover that Deep Blue
>will get the higher rating.  What does this  mean?  It means you there
>is small degree of statistical  confidence that Deep  Blue is a better
>player.  Not much, but some.  And this is EXACTLY what I said.

Actually, you did not say this at all. You said and I quote "The only
scientifically valid conclusion you can draw from this is that it is slightly
more likely that Deep Blue is the better match player".

This is different than what you said in this message: "It means you there is
small degree of statistical confidence that Deep Blue is a better player" (this
was a little garbled, but I think I got the gist).

I agree that there may be a small degree (note the words may and small) of
statistical confidence (not evidence) that Deep Blue is a better match player.
But a statistical conclusion (which is what you originally stated) on this
cannot even be considered.

There is major difference between a statistical conclusion and a statistical
confidence.

Also, consider that after 1 game, Kasparov was in the lead. Through games 2
through 5, they were tied. So, if the sample size would have been smaller, you
may be using the exact same logic to argue that there is a small statistical
confidence that they are virtually equivalent players.

>
>Saying that it  is just as likely that  Kasparov is better because  he
>LOST (huh???) indicates   to me that  you  might need to  brush  up on
>probability and statistics.

I never said this. Please do not put words into my writing. I said that a
statistical CONCLUSION in one direction is just as speculative as in the other
direction.

>
>Your comment does exposes a very common misconception that people have
>when   it  comes to probability  and  statistics.   Your  next comment
>exposes the roots of this, where you seem to indicate that the size of
>the sample tells you whether you  can say something conclusively.  You
>say, "Scientifically speaking, the sample set for either conclusion is
>too small to be  conclusive."  This is  actually true, but the  sample
>size has nothing to do with it unless the sample  size is INFINITE and
>I don't think you meant that, especially  if you don't even understand
>basic probability theory.

Actually, I might surprise you with the amount of probability theory I know as I
used to teach it. As to the size of a sample, it is commonly understood in
statistical theory that you do not need an infinite sized sample to come to a
conclusion. A relatively large sample size (or statement) will do in most cases.

In actuality, for random samplings, it is normally considered that the smallest
number of samples that can even be considered is 5 and the largest is several
hundred. But, of course, it depends on what you are trying to measure and either
extreme is undesirable.

If you use too large of a sample set, it can result in insignificant effects
being measured and assigned significance. For example, let’s say that Kasparov
played Deep Blue 500 times and it was determined that Kasparov loses 1.7% more
times when the games are played before 12 noon than after 12 noon. This
information may be worthless, but worthless or not, it may not necessarily even
be observed in the 6 game match.

If you use too small of a sample set, it can also result in insignificant
effects being measured and assigned significance. Let’s say that you flip a coin
six times and you come up with heads 4 times and tails 2 times. If from this
sample set of data you come up with the conclusion that heads will turn up more
than tails, you are mistaken. Even if you state that you have a statistical
confidence that heads would show up more times than tails, you would be mistaken
(assuming the coin is balanced and flipped from random positions, heights,
etc.).

>
>Now it's possible you  are using the  gray definition of "conclusive."
>You know, the one where you play Kasparov a 24 game match and he beats
>you 24-0.  Then we might  say, "he has proven  conclusively that he is
>the better player."  He hasn't REALLY  proven he is better, but almost
>any fool would bet on him for the second match!  But it doesn't matter
>which definition you  use,  it doesn't  invalidate my   assertion that
>based on the result of the match, it is SLIGHTLY more likely that Deep
>Blue is the better  player.

Again, this is not what you wrote. You may have meant this, but this is not what
you wrote. In fact, it appears that you were using a "gray definition of
conclusive" and really meant that you had a confidence when you first mentioned
it.

>  If you  don't  understand this, then  you
>just don't understand that  a 2800 player   will probably beat  a 1200
>player and you shouldn't be trying to correct people.

My error. I thought I knew the difference between the two.

>
>
>I don't mind being corrected if I am wrong, but at least make sure you
>know what you are talking about.

I don’t mind being corrected if I am wrong, but at least make sure you know what
you are talking about.

KarinsDad :) :)

>
>- Don
>
>
>
>
>
>>Scientifically speaking, the sample set for either conclusion is too small to be
>>conclusive. Statistically, there isn't enough evidence to determine the better
>>match player.
>>
>>KarinsDad
>
>
>
>
>
>
>
>
>
>>>   Anything more than this
>>>is a very fallible judgement call and speculation.
>>>
>>[snip]





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