On Mon, Sep 11, 2000 3:54 AM, Brian J. Beesley <[EMAIL PROTECTED]>
wrote:
>On 11 Sep 00, at 0:31, Robert Deininger wrote:
>> I noticed some exponents where the first-time and double-check results
>> were submitted by the same person, using the same software, on the same
>> machine. If there is a reproducible hardware problem, or one of these
>> "bad" multiplications, then this double-check would not catch an error.
>
>If the offset was different then this would be a valid double check.
Assuming Prime95 was the program that did the test.
>However I agree it is undesirable for the first test and the double
>check for an exponent to be submitted by the same user - though,
>where purely automatic methods of obtaining assignments and reporting
>results were employed, surely it makes no difference.
Don't forget the manually-submitted test results. One way to get the
odd-looking results I saw is to simply submit the same result twice in
succession. If the network or the server is acting up, clicking the
"submit" button more than once is a natural response. In this case the
database might show two LL test results, when only one was actaully done.
It isn't apparent that there is any safeguard against this.
>> Actually, I kind of doubt that the LL test was done twice. More likely
>> one result was accidentally _submitted_ twice, and the friendly primenet
>> server happily accepted both.
>
>Hmm. In this case, if the program was George's, the offset (which is
>not shown in the lucas_v file) would be the same; hopefully George's
>procedure would catch this.
What about the other programs?
The database does record the date and time when a result is submitted. If
the single and double check results came in very close together, it's a
good bet they are not independent. The time isn't in lucas_v, so I can't
tell with the cases I noticed.
>> (We know that the primenet server accepts
>> results from people who do NOT have the exponents assigned to them.)
>
>Is this relevant? More than two different people independently
>testing any given exponent is a probably unneccessary duplication of
>effort, but surely acts to _increase_ confidence in the integrity of
>the database rather than reduce it.
Yes, I think it's relevant. The server seems pretty careful about
assigning
exponents to only one person at a time. It isn't nearly as careful about
accepting results. A bogus double-check result, accidental or otherwise,
would prevent an exponent from ever being assigned to anyone for a real
double-check. That does not increase my confidence!
---------------------------
Robert Deininger
[EMAIL PROTECTED]
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