Response homogeneity groups for a stratified sampling
Computes the response homogeneity groups and the response probability for each unit in these groups for a stratified sampling.
rhg_strata(X,selection)
X |
sample data frame; it should contain the columns 'ID_unit','Stratum', and 'status'; 'ID_unit' denotes the unit identifier (a number); 'Stratum' denotes the unit stratum; 'status' is a 1/0 variable denoting the response/non-response of a unit in the sample. |
selection |
vector of variable names in X used to construct the groups. |
Into a response homogeneity group, the reponse probability is the same for all units. Data are missing at random within groups, conditionally on the selected sample.
The initial sample data frame and also the following components:
rhgroup |
the response homogeneity group for each unit conditionally on its stratum. |
prob_response |
the response probability for each unit; for the units with status=0, this probability is 0. |
Särndal, C.-E., Swensson, B. and Wretman, J. (1992). Model Assisted Survey Sampling. Springer
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## Example 1
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# uses Example 2 from the 'strata' function help file
data=rbind(matrix(rep("nc",165),165,1,byrow=TRUE),matrix(rep("sc",70),70,1,byrow=TRUE))
data=cbind.data.frame(data,c(rep(1,100), rep(2,50), rep(3,15), rep(1,30),rep(2,40)),
1000*runif(235))
names(data)=c("state","region","income")
# draws a sample
s1=strata(data,c("region","state"),size=c(10,5,10,4,6), method="systematic",
pik=data$income)
# extracts the observed data
s1=getdata(data,s1)
# generates randomly the 'status' variable (1-sample respondent, 0-otherwise)
status=runif(nrow(s1))
for(i in 1:length(status))
if(status[i]<0.3) status[i]=0 else status[i]=1
# adds the 'status' variable to the sample data frame s1
s1=cbind.data.frame(s1,status)
# creates classes of income using the median of income
# suppose that the income is available for all units in sample
classincome=numeric(nrow(s1))
for(i in 1:length(classincome))
if(s1$income[i]<median(s1$income)) classincome[i]=1 else classincome[i]=2
# adds 'classincome' to s1
s1=cbind.data.frame(s1,classincome)
# computes the response homogeneity groups using the 'classincome' variable
rhg_strata(s1,selection=c("classincome"))
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## Example 2
############
# the same data as in Example 1
# but we also add the 'sex' column (1-female, 2-male)
# suppose that the sex is available for all units in sample
sex=c(rep(1,12),rep(2,8),rep(1,10),rep(2,5))
s1=cbind.data.frame(s1,sex)
# computes the response homogeneity groups using the 'classincome' and 'sex' variables
rhg_strata(s1,selection=c("classincome","sex"))Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.