brms (version 1.4.0)

mm: Set up multi-membership grouping terms in brms

Description

Function to set up a multi-membership grouping term in brms. The function does not evaluate its arguments -- it exists purely to help set up a model with grouping terms.

Usage

mm(..., weights = NULL)

Arguments

...

One or more terms containing grouping factors.

weights

A matrix specifying the weights of each member. It should have as many columns as grouping terms specified in .... Weights are standardized in order to sum to one per row. If NULL (the default), equally weights are used.

See Also

brmsformula

Examples

## Not run: 
# # simulate some data
# dat <- data.frame(y = rnorm(100), x = rnorm(100), 
#                   g1 = sample(1:10, 100, TRUE),
#                   g2 = sample(1:10, 100, TRUE))
# # multi-membership model with two members per group and equal weights
# fit1 <- brm(y ~ x + (1|mm(g1, g2)), data = dat)
# summary(fit1)
# 
# # weight the first member two times for than the second member
# dat$w1 <- rep(2, 100)
# dat$w2 <- rep(1, 100)
# fit2 <- brm(y ~ x + (1|mm(g1, g2, weights = cbind(w1, w2))), data = dat)
# summary(fit2)
# ## End(Not run)