sscsample {Bolstad} | R Documentation |
Simple, Stratified and Cluster Sampling
Description
Samples from a fixed population using either simple random sampling, stratitified sampling or cluster sampling.
Usage
sscsample(size, n.samples, sample.type="simple", x = NULL, strata = NULL, cluster = NULL, cl.size = NULL, ret=FALSE)
Arguments
size |
the desired size of the sample |
n.samples |
the number of repeat samples to take |
sample.type |
the sampling method. Can be one of "simple", "stratified", "cluser" or 1, 2, 3 where 1 corresponds to "simple", 2 to "stratified" and 3 to "cluster" |
x |
a vector of measurements for each unit in the population. By default x is not used, and the builtin data set sscsample.data is used |
strata |
a corresponding vector for each unit in the population indicating membership to a stratum |
cluster |
a corresponding vector for each unit in the population indicating membership to a cluster |
cl.size |
the number of clusters to sample when using cluster sampling |
ret |
if true then the samples, their means, and the numbers of observations from each stratum are returned as a list. |
Value
If ret is true, then a list will be returned with the following components:
samples |
a matrix with the number of rows equal to size and the number of columns equal to n.samples. Each column corresponds to a sample drawn from the population |
s.strata |
a matrix showing how many units from each stratum were included in the sample |
means |
a vector containing the mean of each sample drawn |
See Also
sscsample.data
Examples
## Draw 200 samples of size 20 using simple random sampling
sscsample(20,200)
## Draw 200 samples of size 20 using simple random sampling and store the
## results. Extract the means of all 200 samples, and the 50th sample
res<-sscsample(20,200,ret=TRUE)
res$means
res$samples[,50]
[Package
Bolstad version 0.1-8
Index]