artlm {ARTool} R Documentation

## Per-Term Linear Model from Aligned Rank Transformed Data

### Description

Build a linear model for ART data with response aligned or aligned and ranked by the specified term from the model.

### Usage

artlm(
m,
term,
response = c("art", "aligned"),
factor.contrasts = "contr.sum",
...
)


### Arguments

 m An object of class art. term A character vector indicating the effect term in the transformed data in m to use as the aligned or art response. response Which response to use: the aligned response ("aligned") or the aligned and ranked ("art") response. factor.contrasts The name of the contrast-generating function to be applied by default to fixed effect factors. Sets the the first element of options("contrasts") for the duration of this function. The default is to use "contr.sum", i.e. sum-to-zero contrasts, which is appropriate for Type III ANOVAs (the default ANOVA type for anova.art). ... Additional arguments passed to lm or lmer.

### Details

This function is used primarily for post-hoc tests. To run an ANOVA, it does not need to be called directly; instead, use anova.art, which calls this function as needed.

### Value

An object of class lm if formula(m) does not contain grouping or error terms, an object of class merMod (i.e. a model fit by lmer) if it contains grouping terms, or an object of class aovlist (i.e. a model fit by aov) if it contains error terms.

### Author(s)

Matthew Kay

See art for an example. See also anova.art, which makes use of this function.