Posterior class probabilities of a mixture fit

For an ordinary mixture() fit, and for a fit of any family that implements the same component interface, such as frmtmb.latent's mixture_mvn() and lca(), one row per observation; for a group-level mixture (groups = ~g), one row per group. The interface is specified under "The mixture component interface" in frmtmb-extension-api.

Usage

mixture_probs(fit)

Arguments

fit

A frmtmb_fit with a mixture family.

Value

A matrix of class probabilities (rows sum to one).

Examples

set.seed(3)
dd <- data.frame(y = c(rnorm(80, 0, 1), rnorm(80, 5, 1)))
fit <- frm(bf(y ~ 1) + mixture(gaussian(), gaussian()), data = dd)

p <- mixture_probs(fit)
head(p)
#>         class1       class2
#> [1,] 1.0000000 4.288987e-08
#> [2,] 0.9999990 1.000118e-06
#> [3,] 0.9999851 1.488386e-05
#> [4,] 1.0000000 1.798825e-08
#> [5,] 0.9999891 1.087896e-05
#> [6,] 0.9999952 4.800314e-06
rowSums(p)[1:3]                    # rows sum to one
#> [1] 1 1 1

# the hard assignment, and how well it recovers the truth
cl <- max.col(p)
table(cl, truth = rep(1:2, each = 80))
#>    truth
#> cl   1  2
#>   1 80  0
#>   2  0 80