get_model_matrix: Get a named model matrix

View source: R/get_model_matrix.R

get_model_matrixR Documentation

Get a named model matrix

Description

Get a named model matrix

Usage

get_model_matrix(model, newdata)

## Default S3 method:
get_model_matrix(model, newdata)

Arguments

model

Model object

newdata

Grid of predictor values at which we evaluate the slopes.

  • Warning: Please avoid modifying your dataset between fitting the model and calling a marginaleffects function. This can sometimes lead to unexpected results.

  • NULL (default): Unit-level slopes for each observed value in the dataset (empirical distribution). The dataset is retrieved using insight::get_data(), which tries to extract data from the environment. This may produce unexpected results if the original data frame has been altered since fitting the model.

  • datagrid() call to specify a custom grid of regressors. For example:

    • newdata = datagrid(cyl = c(4, 6)): cyl variable equal to 4 and 6 and other regressors fixed at their means or modes.

    • See the Examples section and the datagrid() documentation.

  • string:

    • "mean": Marginal Effects at the Mean. Slopes when each predictor is held at its mean or mode.

    • "median": Marginal Effects at the Median. Slopes when each predictor is held at its median or mode.

    • "marginalmeans": Marginal Effects at Marginal Means. See Details section below.

    • "tukey": Marginal Effects at Tukey's 5 numbers.

    • "grid": Marginal Effects on a grid of representative numbers (Tukey's 5 numbers and unique values of categorical predictors).


marginaleffects documentation built on Oct. 20, 2023, 1:07 a.m.