set.seed ( ) function

Hi,

I am using /set.seed()/ ? before the /sample/ ? function.

How does the length of the argument of /set.seed()/ ? and order of the
digits affect how the sampling is carried out?

You can use set.seed() to specify a particular seed so that while
pseudo-random numbers are sampled, you can repeat it.  For example:

set.seed(10)
rnorm(10)
set.seed(10)
rnorm(10)

Specifically, I have used set.seed(123456789). Will this configuration
give me a genuinely random sampling??

You will never get truly random sampling from a computer algorithm,
but it is darn close and more than adequate in the majority of cases.
123456789 is just a length 1 vector containing the number 123456789,
not 9 separate numbers.

Google will be able to give you a lot of information on pseudo-random
number algorithms as well as the concept of "seeds".  Also see
?set.seed

Cheers,

Josh

Thank you in anticipation.

Penny.


? ? ? ?[[alternative HTML version deleted]]

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Joshua Wiley
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University of California, Los Angeles
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