## Randomization.com Help File:

Random Permutations

**The Mechanics of Using the Program**
Specify the smallest and largest integer. The program will provide a
random permutation of all of the integers from the smallest to the
largest.

One of the most common uses is for "drawing names out of a
hat". The random permutation gives the order in which individuals are
selected. For example, to draw 50 individual from a population of 1000,
first order the names of the individuals alphabetically, say, and number
them. Then, generate a random permutation of the integers 1 to 1000.
The first 50 elements of the permutation specify the location of the
chosen individuals in the orginal list. For example, if the random
permutation began 941, 311, 518, then the individuals occupying those
positions in the alphabetical list would be the first three in the
sample.

The **seed** for the random number generator (Wichmann and Hill,
1982, as modified by McLeod, 1985) is obtained from the clock of the
local computer and is printed at the bottom of the randomization plan. If
a seed is included in the request, it overrides the value obtained from
the clock and can be used to reproduce or verify a particular
permutation.

References

McLeod, A. Ian (1985), "Remark AS R58. A remark on algorithm AS 183.
An efficient and portable pseudo-random number generator," Applied
Statistics, 34, 198-200.

Wichmann BA and Hill ID (1982), "Algorithm AS 183. An efficient and
portable pseudo-random number generator," Applied Statistics, 31,
188-190.
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Copyright © 2001 Gerard
E. Dallal