Skip to contents

Condition a moderated network at a moderator value

Source: R/mgm_moderated.R
condition.Rd

Extracts the effective pairwise network implied by a moderated MGM (mgm_fit() with moderators) at a given value of the moderator, mirroring mgm::condition(): it applies the AND-rule pre-filter, absorbs the moderator value into the main-effect coefficients, and re-aggregates the pairwise edges.

Usage

condition(object, value, rule = NULL)

Arguments

object

A psychnet_moderated object from mgm_fit(..., moderators=).

value

Moderator value to condition on (e.g. 0 or 1 for a binary moderator, or any numeric for a continuous one).

rule

Symmetrization rule; defaults to the rule used at fit time.

Value

A psychnet network object (the moderator node carries no edges).

Examples

set.seed(1)
x1 <- stats::rnorm(400); x2 <- stats::rnorm(400)
mod <- rep(0:1, each = 200)
y <- x1 * (mod == 1) + stats::rnorm(400)   # x1-y edge only when mod == 1
d <- data.frame(x1 = x1, x2 = x2, y = y, mod = mod)
fit <- mgm_fit(d, types = c("g", "g", "g", "c"), moderators = 4)
condition(fit, value = 0)   # no x1-y edge
#> <psychnet> mgm_moderated network
#>   nodes: 4   edges: 0   (undirected)
condition(fit, value = 1)   # the x1-y edge appears
#> <psychnet> mgm_moderated network
#>   nodes: 4   edges: 1   (undirected)