Compute partial residuals from a data grid — residualize_over

This function computes partial residuals based on a data grid, where the data grid is usually a data frame from all combinations of factor variables or certain values of numeric vectors. This data grid is usually used as newdata argument in predict(), and can be created with insight::get_datagrid().

Usage

residualize_over_grid(grid, model, ...)

# S3 method for class 'data.frame'
residualize_over_grid(grid, model, predictor_name, ...)

Arguments

grid: A data frame representing the data grid, or an object of class estimate_means or estimate_predicted, as returned by the different estimate_*() functions.
model: The model for which to compute partial residuals. The data grid grid should match to predictors in the model.
...: Currently not used.
predictor_name: The name of the focal predictor, for which partial residuals are computed.

Value

A data frame with residuals for the focal predictor.

Partial Residuals

For generalized linear models (glms), residualized scores are computed as inv.link(link(Y) + r) where Y are the predicted values on the response scale, and r are the working residuals.

For (generalized) linear mixed models, the random effect are also partialled out.

References

Fox J, Weisberg S. Visualizing Fit and Lack of Fit in Complex Regression Models with Predictor Effect Plots and Partial Residuals. Journal of Statistical Software 2018;87.

Examples

set.seed(1234)
x1 <- rnorm(200)
x2 <- rnorm(200)
# quadratic relationship
y <- 2 * x1 + x1^2 + 4 * x2 + rnorm(200)

d <- data.frame(x1, x2, y)
model <- lm(y ~ x1 + x2, data = d)

pr <- estimate_means(model, c("x1", "x2"))
head(residualize_over_grid(pr, model))
#>          x1    x2     Mean
#> 37   -0.889 0.814 1.668084
#> 57    0.422 0.814 4.203154
#> 66    1.077 0.112 3.374450
#> 17   -2.200 0.814 3.450142
#> 56    0.422 0.112 1.943842
#> 57.1  0.422 0.814 4.484100