Simpson's paradox, or the Yule-Simpson effect, is a phenomenon in probability and statistics, in which a trend appears in several different groups of data but disappears or reverses when these groups are combined.

simulate_simpson(
  n = 100,
  r = 0.5,
  groups = 3,
  difference = 1,
  group_prefix = "G_"
)

Arguments

n

The number of observations for each group to be generated (minimum 4).

r

A value or vector corresponding to the desired correlation coefficients.

groups

Number of groups (groups can be participants, clusters, anything).

difference

Difference between groups.

group_prefix

The prefix of the group name (e.g., "G_1", "G_2", "G_3", ...).

Value

A dataset.

Examples

data <- simulate_simpson(n = 10, groups = 5, r = 0.5) if (require("ggplot2")) { ggplot(data, aes(x = V1, y = V2)) + geom_point(aes(color = Group)) + geom_smooth(aes(color = Group), method = "lm") + geom_smooth(method = "lm") }
#> `geom_smooth()` using formula 'y ~ x'
#> `geom_smooth()` using formula 'y ~ x'