R help - Nov 2008 - (no subject)

I need help with another problem I am having that deals with the generation of
vectors that I asked about yesterday.  I now need to have each value in the
vector (all values either 1 or -1) have a probability p that it will switch
signs (so, say, each value has a 50% chance of switching from -1 to 1 or visa
versa).  What would be the best way to go about doing this?  Thank-you!!

Salas, Andria Kay <aks2515 at uncw.edu> [Tue, Nov 18, 2008 at 04:10:06PM
CET]:
> I need help with another problem I am having that deals with the generation
of vectors that I asked about yesterday.  I now need to have each value in the
vector (all values either 1 or -1) have a probability p that it will switch
signs (so, say, each value has a 50% chance of switching from -1 to 1 or visa
versa).  What would be the best way to go about doing this?  Thank-you!!
Say you have a vector v, you can generate another vector randomly by

w <- sample(c(-1, 1), length(v), replace=TRUE)

and multiply v with w.

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