Hello,
I'm going to use R to analyze some point count data and I need to use the
sample function. Let's say that I have a data set like below with each row
being a visit to a site and the numbers in the rows individual distances.
The real data set will of course have many more rows.
>a
[[1]]
[1] 1 10 2 32 43 54 65 NA
[[2]]
[1] 2 1 32 6 5 44 3 2
[[3]]
[1] 3 3 22 56 7 NA NA NA
[[4]]
[1] 4 23 4 33 NA NA NA NA
[[5]]
[1] 5 22 12 2 2 2 32 NA
[[6]]
[1] 6 22 32 43 23 5 NA NA
I'm going to analyze how density changes with number of visits. So I will
sample 1 visit (row) x number of times and export the distances to the
program DISTANCE. I know that I can do the sampling part using:
sample(a,x,replace=TRUE,prob=NULL) This works fine. But I also need to
sample 2 visits (rows) out of visits 1-3 and then 2 visits out of visits
4-6, and so on x number of times. Any ideas?
Thanks much,
Nathan Cooper
Utah Division of Wildlife Resources
nathanwands at hotmail.com
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