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Re: Obtaining random bit sequences from throwing a die
Posted:
Jan 31, 2013 3:47 PM


On 20130131, MokKong Shen <mokkong.shen@tonline.de> wrote: > I have a further question. Is there anything against the following?
> 1 > 00 > 2 > 01 > 3 > 10 > 4 > 11 > 5 > 0 > 6 > 1
> M. K. Shen
This will have the desired property, but you are only getting 5/3 bits per roll. If two rolls at a time were considered, the expected number would be 7/3 per roll.
If one has a random integer uniformly distributed from 0 to n1, a most efficient manner of getting random bits from it is to compare the binary expansion of it with that of n. There is a first point of difference, and all subsequent bits can be used as binary random bits. If one uses that method for n=6, and reduce the number observed by 1, the posted result will be what is obtained. Less than 2 bits on the average are lost this way.
 This address is for information only. I do not claim that these views are those of the Statistics Department or of Purdue University. Herman Rubin, Department of Statistics, Purdue University hrubin@stat.purdue.edu Phone: (765)4946054 FAX: (765)4940558



