| Version: | 1.0 |
| Date: | 2021-01-14 |
| Title: | PPS Sampling |
| Author: | Jack G. Gambino <jack.gambino@gmail.com> |
| Maintainer: | Jack G. Gambino <jack.gambino@gmail.com> |
| Description: | Functions to select samples using PPS (probability proportional to size) sampling. The package also includes a function for stratified simple random sampling, a function to compute joint inclusion probabilities for Sampford's method of PPS sampling, and a few utility functions. The user's guide pps-ug.pdf is included in the .../pps/doc directory. The methods are described in standard survey sampling theory books such as Cochran's "Sampling Techniques"; see the user's guide for references. |
| License: | GPL-2 | GPL-3 [expanded from: GPL (≥ 2)] |
| NeedsCompilation: | no |
| Packaged: | 2021-01-16 18:19:30 UTC; jackg |
| Repository: | CRAN |
| Date/Publication: | 2021-01-17 05:50:02 UTC |
California places
Description
See user's guide
Note
See the user's guide, pps-ug.pdf, for more information.
California counties
Description
See user's guide
Note
See the user's guide, pps-ug.pdf, for more information.
Randomize units within strata
Description
Randomize the order of units within each stratum
Usage
permuteinstrata(stratsizes)Arguments
stratsizes |
A vector containing the size of each stratum |
Value
Returns the vector of permuted indices. In the example below, the returned vector has 29 elements.
Note
See the user's guide, pps-ug.pdf, for more information.
Examples
stratsizes <- c(9,10,10) # strata have 9, 10 and 10 units, respectively
permuteinstrata(stratsizes)
Select one unit with PPS
Description
Use PPS systematic sampling to select a single unit out of N
Usage
pps1(sizes)Arguments
sizes |
A vector of the sizes of the units in the population |
Value
Returns the index of the unit that was selected
Note
See the user's guide, pps-ug.pdf, for more information.
Examples
sizes <- c(9,2,5,17,4,21,15,7,4,11,23,23,14)
sampleindex <- pps1(sizes)
PPS systematic sampling
Description
Use PPS systematic sampling to select a sample of n units out of N
Usage
ppss(sizes,n)Arguments
sizes |
A vector of the sizes of the units in the population |
n |
The sample size |
Value
Returns the indices of the units that were selected in the sample
Note
See the user's guide, pps-ug.pdf, for more information.
Examples
sizes <- c(9,2,5,17,4,21,15,7,4,11,23,23,14)
sampleindices <- ppss(sizes,4)
Stratified PPS systematic sampling
Description
In each stratum, select a sample using pps systematic sampling
Usage
ppssstrat(sizes,stratum,n)Arguments
sizes |
A vector of the sizes of the units in the population, sorted by stratum |
stratum |
A vector of stratum codes, in the same order |
n |
A vector containing the sample size in each stratum |
Value
Returns the indices of the units that were selected in the sample
Note
ppssstrat calls ppss once per stratum.
See the user's guide, pps-ug.pdf, for more information.
Examples
sizes <- c(1:5,10:6)*10
strat <- c(1,1,1,2,2,3,3,3,3,3)
n <- c(2,1,3)
ppssstrat(sizes,strat,n)
PPS sampling with replacement
Description
Use PPS sampling to select a sample of n units out of N with replacement
Usage
ppswr(sizes,n)Arguments
sizes |
A vector of the sizes of the units in the population |
n |
The sample size |
Value
Returns the indices of the units that were selected in the sample
Note
See the user's guide, pps-ug.pdf, for more information.
Examples
sizes <- c(9,2,5,17,4,21,15,7,4,11,23,23,14)
sampleindices <- ppswr(sizes,4)
Sampford's PPS sampling method
Description
Use Sampford's method to select a PPS sample of units
Usage
sampford(size,n)Arguments
size |
A vector of the sizes of the units in the population |
n |
The sample size |
Value
Returns the indices of the units that were selected in the sample
Note
The function sampfordpi can be used to compute joint inclusion
probabilities for this method.
See the user's guide, pps-ug.pdf, for more information.
Examples
size <- c(9,2,5,17,4,21,15,7,4,11,23,23,14)
sampleindices <- sampford(size,4)
Joint inclusion probabilities for Sampford's PPS sampling method
Description
Compute joint inclusion probabilities for Sampford's method of PPS sampling
Usage
sampfordpi(sizes,n)Arguments
sizes |
A vector of the sizes of the units in the population |
n |
The sample size |
Value
Returns a matrix with the inclusion probability pi(i) for each unit i in the population and with the joint inclusion probability pi(i,j) of units i and j in position (i,j) in the matrix, where i and j are not equal. Note that the size of the matrix is NxN, where N is the population size.
Note
The function sampford can be used to select a sample
using Sampford's method.
See the user's guide, pps-ug.pdf, for more information.
Examples
sizes <- c(9,2,5,17,4,21,15,7,4,11,23,23,14)
piij <- sampfordpi(sizes,4)
weights <- 1/diag(piij) # the weights one would use for estimation
Check that unit sizes are not too big
Description
See user's guide
Usage
sizesok(size,n)Arguments
size |
A vector of the sizes of the units in the population |
n |
The sample size |
Value
Returns the number of 'bad' units
Note
See the user's guide, pps-ug.pdf, for more information.
Stratified simple random sampling
Description
In each stratum, select a simple random sample
Usage
stratsrs(stratum,nh)Arguments
stratum |
A vector of stratum codes, sorted by stratum |
nh |
A vector containing the sample size in each stratum |
Value
Returns the indices of the units that were selected in the sample
Note
See the user's guide, pps-ug.pdf, for more information.
Examples
strat <- c(1,1,1,1,1,2,2,2,3,3,3,3,3,3,3) # stratum 1 has 5 units, etc.
nh <- c(2,1,3) # select 2 units from stratum 1, 1 from stratum 2 and 3 from 3
stratsrs(strat,nh)
Compute size of each stratum
Description
Given a vector of sorted stratum indicators, returns the number of units in each stratum
Usage
stratumsizes(stratum)Arguments
stratum |
A vector of sorted stratum indicators |
Value
Returns the number of units in each stratum
Note
See the user's guide, pps-ug.pdf, for more information.