mersenneforum.org what are Reliability and Confidence?
 User Name Remember Me? Password
 Register FAQ Search Today's Posts Mark Forums Read

 2015-10-20, 07:57 #1 dragonbud20     Mar 2014 24·5 Posts what are Reliability and Confidence? I was looking at the specific setting for my computer on the website and I noticed these two values as well as CPU rolling average. I believe I've seen Reliability and Confidence mentioned before and I was wondering what they all meant.
 2015-10-20, 10:39 #2 MattcAnderson     "Matthew Anderson" Dec 2010 Oregon, USA 19×31 Posts Hi Math People, That is a good question. Although I am not intimately familiar with the inner workings of Prime95, I offer two Wikipedia articles. Reliability - https://en.wikipedia.org/wiki/Reliability Confidence - https://en.wikipedia.org/wiki/Confidence In My Humble Opinion (IMHO), Wikipedia is a great free encyclopedia. Thanks again for the question. Regards, Matt
 2015-10-20, 11:43 #3 Mini-Geek Account Deleted     "Tim Sorbera" Aug 2006 San Antonio, TX USA 17×251 Posts Reliability is a measure of how likely your computer is to produce a correct result. Confidence is how sure PrimeNet is of that reliability figure. For example, when you start out, you'll probably have a good reliability measure, but with very low confidence (i.e. we can only guess you're good). If you consistently return error-free results (either because of a matching DC or just from the error tracking during the test), the reliability and confidence get higher (i.e. we know you're good). If you consistently return bad results, the reliability gets lower and the confidence goes up (i.e. we know you're bad).
 2015-10-20, 22:22 #4 dragonbud20     Mar 2014 24·5 Posts Do you have any idea what the ranges of the values are? my reliability is .98 which I presume is a percentage and the confidence is 10.0 my first assumption would be statistical confidence but that doesn't really make sense in this context.
2015-10-20, 23:04   #5
Mini-Geek
Account Deleted

"Tim Sorbera"
Aug 2006
San Antonio, TX USA

17·251 Posts

Quote:
 Originally Posted by dragonbud20 Do you have any idea what the ranges of the values are? my reliability is .98 which I presume is a percentage and the confidence is 10.0 my first assumption would be statistical confidence but that doesn't really make sense in this context.
I found some details on it.

Reliability is a rolling average, and is a percentage like you thought and so would range from 0-1: yours means that it thinks there's a 98% probability that a result you give is correct (probably uncoincidentally, 0.98 is the score given for an unverified but no-errors-reported LL test, like most first-time LLs). Confidence is just a count of how many LL tests you've returned, so yours means you've done 10 tests (this is more simplistic than confidence intervals). A more advanced confidence test should include the estimated time of the LL test, but that level of precision isn't really needed for GIMPS's purposes.

See also the thresholds page that has some reliability/confidence levels (in short, a confidence of 2.0 or above and a reliability of 0.95 or higher is good enough for anything).

Last fiddled with by Mini-Geek on 2015-10-20 at 23:19

 2015-10-20, 23:19 #6 dragonbud20     Mar 2014 24·5 Posts Thanks for the help in tracking that info down
2015-10-20, 23:20   #7
chalsall
If I May

"Chris Halsall"
Sep 2002
Barbados

25·281 Posts

Quote:
 Originally Posted by dragonbud20 Do you have any idea what the ranges of the values are? my reliability is .98 which I presume is a percentage and the confidence is 10.0 my first assumption would be statistical confidence but that doesn't really make sense in this context.
Some empirical data: One of my absolutely trustworthy machines (no errors, only does Double Checks, thousands of results) has a reliability of .98 and a confidence of 10.0.

It would be, indeed, interesting to have an explication as to the maths behind these numbers...

2015-10-21, 00:41   #8
kladner

"Kieren"
Jul 2011
In My Own Galaxy!

100110011101102 Posts

Quote:
 Originally Posted by chalsall Some empirical data: One of my absolutely trustworthy machines (no errors, only does Double Checks, thousands of results) has a reliability of .98 and a confidence of 10.0. It would be, indeed, interesting to have an explication as to the maths behind these numbers...
My only system, which has committed a variety of errors, though not recently, also has .98 reliability and confidence 10. I don't believe confidence goes above 10. I assume that my system has done enough good work, since the last bad spell, for the rating system to max out.

 2015-10-21, 01:19 #9 snme2pm1   "Graham uses ISO 8601" Mar 2014 AU, Sydney 23×29 Posts My confidence took a tumble after 4 of 4 cores returned bad results from double check 34M work on almost the same day not long ago. That has been the only known problem for such work. As I look now after a little more DC work, I see Reliability, Confidence 0.98, 10.0. P.S. I was referring to my personal confidence, I didn't note to what extent PrimeNet blinked. Last fiddled with by snme2pm1 on 2015-10-21 at 01:30
 2015-10-21, 02:30 #10 LaurV Romulan Interpreter     Jun 2011 Thailand 8,539 Posts To contribute some data, all computers in my list have a 0.98, 10.0, except two. From the two, one is 0.99, 10.0 (Yaaarrrr! ) The other is a "split", or "clone" which means (quote from the web page) "The server may erroneously create a duplicate entry for one of your computers. This isn't harmful, but can result in some confusion having two entries for the same computer in the table above. This "cloning" can occur if you upgrade a computer's CPU, upgrade or re-install Windows, or run into a program bug. You can merge the two entries by checking two computers above, checking the "I am sure" box, and clicking the merge button." This "split" shows a 0.98, 2.0 initially, but then I "merged" it (luckily, the computer is still there, and the "clone" didn't report anything since end of June, I assume the server got confused by my July holiday). After merging it with the original, the score of the original is still 0.98, 10.0 (no "average" was done, I was a bit afraid it will do that). Last fiddled with by LaurV on 2015-10-21 at 02:32
2015-10-21, 03:26   #11
kladner

"Kieren"
Jul 2011
In My Own Galaxy!

2·32·547 Posts

Quote:
 Originally Posted by snme2pm1 ..... P.S. I was referring to my personal confidence, I didn't note to what extent PrimeNet blinked.

 Thread Tools

 Similar Threads Thread Thread Starter Forum Replies Last Post AlexJohn73 Information & Answers 4 2015-11-22 09:26 tha PrimeNet 36 2013-12-06 09:23 lidocorc Information & Answers 6 2009-08-11 04:04 lidocorc Hardware 8 2009-03-24 12:38 Cruelty Riesel Prime Search 3 2006-02-15 05:15

All times are UTC. The time now is 13:59.

Mon Jun 1 13:59:33 UTC 2020 up 68 days, 11:32, 2 users, load averages: 1.95, 1.80, 1.76

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.

This forum has received and complied with 0 (zero) government requests for information.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation.
A copy of the license is included in the FAQ.