Fixed block randomization. The block input should repeat each
treatment code the number of times it is to be included within each block.
The final block will be a partial block if n is not an exact multiple
of the block length.
Usage
randomize_by_fixed_block(n = 10, block = c(0, 0, 1, 1))Value
A treatment group sequence (vector) of length n with
treatments from block permuted within each block having
block size equal to the length of block.
Examples
library(dplyr)
# Example 1
# 2:1 randomization with block size 3, treatments "A" and "B"
data.frame(x = 1:10) |> mutate(Treatment = randomize_by_fixed_block(block = c("A", "B", "B")))
#> x Treatment
#> 1 1 A
#> 2 2 B
#> 3 3 B
#> 4 4 B
#> 5 5 A
#> 6 6 B
#> 7 7 B
#> 8 8 B
#> 9 9 A
#> 10 10 A
# Example 2
# Stratified randomization
data.frame(stratum = c(rep("A", 10), rep("B", 10))) |>
group_by(stratum) |>
mutate(Treatment = randomize_by_fixed_block())
#> # A tibble: 20 × 2
#> # Groups: stratum [2]
#> stratum Treatment
#> <chr> <dbl>
#> 1 A 1
#> 2 A 1
#> 3 A 0
#> 4 A 0
#> 5 A 0
#> 6 A 0
#> 7 A 1
#> 8 A 1
#> 9 A 0
#> 10 A 0
#> 11 B 1
#> 12 B 0
#> 13 B 0
#> 14 B 1
#> 15 B 1
#> 16 B 1
#> 17 B 0
#> 18 B 0
#> 19 B 0
#> 20 B 0