One-way Contrast

Create a one-way contrast specification

Usage

oneway_contrast(A, name, where = NULL, basis = NULL, basis_weights = NULL)

Arguments

A

A formula specifying the contrast

name

The name of the contrast

where

An optional formula specifying the subset over which the contrast is computed.

basis

NULL (default: use all basis functions), an integer vector specifying which basis function indices to include, or "all". See pair_contrast for details on basis filtering.

basis_weights

NULL (default: equal weights), or a numeric vector of weights to apply to the selected basis functions. Must have the same length as basis selection and will be normalized to sum to 1. See pair_contrast for details on basis weighting.

Value

A oneway_contrast_spec object that can be used to generate contrast weights

See also

interaction_contrast for testing interactions, pair_contrast for pairwise comparisons

Examples

# Create a one-way contrast for a factor 'basis'
con <- oneway_contrast(~ basis, name = "Main_basis")

# Create a one-way contrast with a 'where' clause
con <- oneway_contrast(~ basis, name = "Main_basis",
                      where = ~ block == 1)

# Test only first two basis functions
con <- oneway_contrast(~ condition, name = "Main_early", basis = 1:2)