Obtain the Number of Possible Permutations from a Random Assignment Declaration

Usage

obtain_num_permutations(declaration)

Arguments

declaration: A random assignment or sampling declaration, created by declare_ra or declare_rs.

Value

a scalar

Examples


# Random assignment
## complete

declaration <- declare_ra(N = 4)
perms <- obtain_permutation_matrix(declaration)
dim(perms)
#> [1] 4 6
obtain_num_permutations(declaration)
#> [1] 6

## blocked

blocks <- c("A", "A", "B", "B", "C", "C", "C")
declaration <- declare_ra(blocks = blocks)
perms <- obtain_permutation_matrix(declaration)
dim(perms)
#> [1]  7 24
obtain_num_permutations(declaration)
#> [1] 24

## clustered

clusters <- c("A", "B", "A", "B", "C", "C", "C")
declaration <- declare_ra(clusters = clusters)
perms <- obtain_permutation_matrix(declaration)
dim(perms)
#> [1] 7 6
obtain_num_permutations(declaration)
#> [1] 6

## large

declaration <- declare_ra(20)
choose(20, 10)
#> [1] 184756
perms <- obtain_permutation_matrix(declaration)
dim(perms)
#> [1]    20 10000

# Random sampling
## complete

declaration <- declare_rs(N = 4)
perms <- obtain_permutation_matrix(declaration)
dim(perms)
#> [1] 4 6
obtain_num_permutations(declaration)
#> [1] 6

## stratified

strata <- c("A", "A", "B", "B", "C", "C", "C")
declaration <- declare_rs(strata = strata)
perms <- obtain_permutation_matrix(declaration)
dim(perms)
#> [1]  7 24
obtain_num_permutations(declaration)
#> [1] 24

## clustered

clusters <- c("A", "B", "A", "B", "C", "C", "C")
declaration <- declare_rs(clusters = clusters)
perms <- obtain_permutation_matrix(declaration)
dim(perms)
#> [1] 7 6
obtain_num_permutations(declaration)
#> [1] 6

## large

declaration <- declare_rs(N = 20)
perms <- obtain_permutation_matrix(declaration)
dim(perms)
#> [1]    20 10000