[R] Sample selection problem

Jenny Barnes jmb at mssl.ucl.ac.uk
Wed Oct 3 13:54:25 CEST 2007


Can't you do something like:

x <- c(1,1,1,1,1,1,0,0,0,0)
sample(x, 30, T)

Best Wishes,


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>I want to get a sample of some arbitrary size from a population having only two 
values 0 and 1 with replacement, but with different probability for selection. 
For example 0 will be selected with probability 0.4 and 1 with 0.6. I could use 
sample function i.e. sample(c(0,1), 30, T) to get this, however here, selection 
of either 0 or 1 has equal probability here. I am looking for a function which 
can do the same thing but with different probabilities.
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Jennifer Barnes
PhD student: long range drought prediction 
Climate Extremes Group
Department of Space and Climate Physics
University College London
Holmbury St Mary 
Dorking, Surrey, RH5 6NT
Tel: 01483 204149
Mob: 07916 139187
Web: http://climate.mssl.ucl.ac.uk

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