Domains {TeachingSampling}

Domains Indicator Matrix

Description

Creates a matrix of domain indicator variables for every single unit in the selected sample or in the entire population

Usage

Domains(y)

Arguments

y

Vector of the domain of interest containing the membership of each unit to a specified category of the domain

Details

Each value of y represents the domain which a specified unit belongs

Value

The function returns a n\times p matrix, where n is the number of units in the selected sample and p is the number of categories of the domain of interest. The values of this matrix are zero, if the unit does not belongs to a specified category and one, otherwise.

Author(s)

Hugo Andres Gutierrez Rojas [e-mail]

References

Sarndal, C-E. and Swensson, B. and Wretman, J. (1992), Model Assisted Survey Sampling. Springer.
Gutierrez, H. A. (2009), Estrategias de muestreo: Diseno de encuestas y estimacion de parametros. Editorial Universidad Santo Tomas.

See Also

E.SI

Examples

############
## Example 1
############
# This domain contains only two categories: "yes" and "no"
x <- as.factor(c("yes","yes","yes","no","no","no","no","yes","yes"))
Domains(x)

############
## Example 2
############
# Uses the Lucy data to draw a random sample of units according 
# to a SI design
data(Lucy)
attach(Lucy)

N <- dim(Lucy)[1]
n <- 400
sam <- sample(N,n)
# The information about the units in the sample is stored in an object called data
data <- Lucy[sam,]
attach(data)
names(data)
# The variable SPAM is a domain of interest
Doma <- Domains(SPAM)
Doma
# HT estimation of the absolute domain size for every category in the domain
# of interest
E.SI(N,n,Doma)

############
## Example 3
############
# Following with Example 2... 
# The variables of interest are: Income, Employees and Taxes
# This function allows to estimate the population total of this variables for every 
# category in the domain of interest SPAM 
estima <- data.frame(Income, Employees, Taxes)
SPAM.no <- estima*Doma[,1]
SPAM.yes <- estima*Doma[,2]
E.SI(N,n,SPAM.no)
E.SI(N,n,SPAM.yes)