Re: New random discoveries?
This WebDNA talk-list message is from 2005
It keeps the original formatting.
numero = 60706
interpreted = N
texte = Justin Carroll wrote: > I've created a banner rotating system and have noticed that random > isn't so random just like many people have on the talk-list. There are lot of reason why "ra" doesn't do what you think it does: 1) Random numbers in computers are rarely truly random (unless you have a new enough CPU with a hardware random generator); some O/S's provide a very weak random number library (which can run out of randomness), so if you are using SSL, you can actually be reducing your available randomness for other purposes. 2) Random numbers can only be measured over large sequences (i.e. it is perfectly OK to have 10 consecutive repeats of a single number as long as the average over many millions is no more or less than any number single number). 3) Rotating banner ads are far more likely to be fair (or made fair) than relying on a random number to choose a banner to display. John -- John Peacock Director of Information Research and Technology Rowman & Littlefield Publishing Group 4501 Forbes Boulevard Suite H Lanham, MD 20706 301-459-3366 x.5010 fax 301-429-5748 ------------------------------------------------------------- This message is sent to you because you are subscribed to the mailing list
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Associated Messages, from the most recent to the oldest:
Justin Carroll wrote: > I've created a banner rotating system and have noticed that random > isn't so random just like many people have on the talk-list. There are lot of reason why "ra" doesn't do what you think it does: 1) Random numbers in computers are rarely truly random (unless you have a new enough CPU with a hardware random generator); some O/S's provide a very weak random number library (which can run out of randomness), so if you are using SSL, you can actually be reducing your available randomness for other purposes. 2) Random numbers can only be measured over large sequences (i.e. it is perfectly OK to have 10 consecutive repeats of a single number as long as the average over many millions is no more or less than any number single number). 3) Rotating banner ads are far more likely to be fair (or made fair) than relying on a random number to choose a banner to display. John -- John Peacock Director of Information Research and Technology Rowman & Littlefield Publishing Group 4501 Forbes Boulevard Suite H Lanham, MD 20706 301-459-3366 x.5010 fax 301-429-5748 ------------------------------------------------------------- This message is sent to you because you are subscribed to the mailing list . To unsubscribe, E-mail to: To switch to the DIGEST mode, E-mail to Web Archive of this list is at: http://webdna.smithmicro.com/
John Peacock
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