Randomly sample pairs of writing samples

This function samples a subset of rows from a pairs data frame returned by make_pairs. You can specify either the proportion of pairs to retain (pair_pct), the absolute number of pairs (n_pairs), or both (in which case the minimum of the two is used).

Usage

sample_pairs(pairs, pair_pct = 1, n_pairs = NULL, seed = NULL)

Arguments

pairs

A tibble with columns ID1, text1, ID2, and text2.

pair_pct

Proportion of pairs to sample (between 0 and 1). Defaults to 1 (all pairs).

n_pairs

Optional integer specifying the maximum number of pairs to sample.

seed

Optional integer seed for reproducible sampling.

Value

A tibble containing the sampled rows of pairs.

Details

A random subset does not guarantee that every item participates or that all items are connected through comparisons. Inspect the design before using the collected outcomes to rank a complete set.

See also

read_samples_df(), read_samples_dir()

Other pairing and data: alternate_pair_order(), make_pairs(), randomize_pair_order(), read_samples_df(), read_samples_dir(), sample_reverse_pairs()

Examples

samples <- tibble::tibble(
  ID   = c("S1", "S2", "S3", "S4"),
  text = paste("Sample", 1:4)
)
pairs_all <- make_pairs(samples)

# Sample 50% of all pairs
sample_pairs(pairs_all, pair_pct = 0.5, seed = 123)
#> # A tibble: 3 × 4
#>   ID1   text1    ID2   text2   
#>   <chr> <chr>    <chr> <chr>   
#> 1 S1    Sample 1 S4    Sample 4
#> 2 S3    Sample 3 S4    Sample 4
#> 3 S1    Sample 1 S3    Sample 3

# Sample exactly 3 pairs
sample_pairs(pairs_all, n_pairs = 3, seed = 123)
#> # A tibble: 3 × 4
#>   ID1   text1    ID2   text2   
#>   <chr> <chr>    <chr> <chr>   
#> 1 S1    Sample 1 S4    Sample 4
#> 2 S3    Sample 3 S4    Sample 4
#> 3 S1    Sample 1 S3    Sample 3

# Using built-in examples and sample 10% of all pairs
data("example_writing_samples")
pairs_ex <- make_pairs(example_writing_samples)
pairs_ex_sample <- sample_pairs(pairs_ex, pair_pct = 0.10, seed = 1)
nrow(pairs_ex_sample)
#> [1] 19