Add random factors to a data structure
add_random(.data = NULL, ..., .nested_in = NULL)the data frame
the new random factor column name and the number of values of the random factor (if crossed) or the n per group (if nested); can be a vector of n per group if nested
the column(s) to nest in (if NULL, the factor is crossed with all columns)
a data frame
# start a data frame
data1 <- add_random(school = 3)
# nest classes in schools (2 classes per school)
data2 <- add_random(data1, class = 2, .nested_in = "school")
# nest pupils in each class (different n per class)
data3 <- add_random(data2, pupil = c(20, 24, 23, 21, 25, 24), .nested_in = "class")
# cross each pupil with 10 questions
data4 <- add_random(data3, question = 10)
# compare nesting in 2 different factors
data <- add_random(A = 2, B = 2)
add_random(data, C = 2, .nested_in = "A")
#> # A tibble: 8 × 3
#> A B C
#> <chr> <chr> <chr>
#> 1 A1 B1 C1
#> 2 A1 B1 C2
#> 3 A1 B2 C1
#> 4 A1 B2 C2
#> 5 A2 B1 C3
#> 6 A2 B1 C4
#> 7 A2 B2 C3
#> 8 A2 B2 C4
add_random(data, C = 2, .nested_in = "B")
#> # A tibble: 8 × 3
#> A B C
#> <chr> <chr> <chr>
#> 1 A1 B1 C1
#> 2 A1 B1 C2
#> 3 A1 B2 C3
#> 4 A1 B2 C4
#> 5 A2 B1 C1
#> 6 A2 B1 C2
#> 7 A2 B2 C3
#> 8 A2 B2 C4
# specify item names
add_random(school = c("Hyndland Primary", "Hyndland Secondary")) %>%
add_random(class = list(paste0("P", 1:7),
paste0("S", 1:6)),
.nested_in = "school")
#> # A tibble: 13 × 2
#> school class
#> <chr> <chr>
#> 1 Hyndland Primary P1
#> 2 Hyndland Primary P2
#> 3 Hyndland Primary P3
#> 4 Hyndland Primary P4
#> 5 Hyndland Primary P5
#> 6 Hyndland Primary P6
#> 7 Hyndland Primary P7
#> 8 Hyndland Secondary S1
#> 9 Hyndland Secondary S2
#> 10 Hyndland Secondary S3
#> 11 Hyndland Secondary S4
#> 12 Hyndland Secondary S5
#> 13 Hyndland Secondary S6