Extract fitted values from a count regression model

Returns the vector of fitted values from any model class produced by poissonGLM(), negbinGLM(), quasiPoissonGLM(), tweedieGLM(), zeroinflPoissonGLM(), zeroinflNegbinGLM(), zeroinflTweedieGLM(), or countGLM(). For countGLM() objects, fitted values are taken from the selected best model.

Usage

# S3 method for class 'countGLMfit'
fitted(object, ...)

# S3 method for class 'countGLM'
fitted(object, ...)

Arguments

object: A fitted model returned by any of the package fitters, or a countGLM comparison object.
...: Additional arguments passed to the underlying backend's fitted() method.

Value

A numeric vector of fitted means on the response scale.

Examples

df <- data.frame(
  y  = c(0L, 1L, 2L, 3L, 5L, 0L, 2L, 4L, 1L, 3L),
  x1 = c(1.2, -0.4, 0.8, -1.1, 2.0, 0.3, -0.9, 1.5, -0.2, 0.7)
)
fit <- poissonGLM(y ~ x1, data = df)
#> Warning: Count component: 8 events (y > 0) for 1 predictor(s) (8.0 per predictor). At least 10 events per predictor is recommended.
head(fitted(fit))
#>        1        2        3        4        5        6 
#> 2.554880 1.600319 2.272896 1.304135 3.228141 1.963771