glht-support: Support for 'multcomp::glht'

In emmeans: Estimated Marginal Means, aka Least-Squares Means

Support for multcomp::glht

Description

These functions and methods provide an interface between emmeans and the multcomp::glht function for simultaneous inference provided by the multcomp package.

Usage

emm(...)

as.glht(object, ...)

## S3 method for class 'emmGrid'
as.glht(object, ...)

Arguments

...	In emm, the specs, by, and contr arguments you would normally supply to emmeans. Only specs is required. Otherwise, arguments are passed to other methods. You may also include a which argument; see Details.
object	An object of class emmGrid or emm_list

Value

emm returns an object of an intermediate class for which there is a multcomp::glht method.

as.glht returns an object of class glht or glht_list according to whether object is of class emmGrid or emm_list. See Details below for more on glht_lists.

Details for emm

emm is meant to be called only from "glht" as its second (linfct) argument. It works similarly to multcomp::mcp, except with specs (and optionally by and contr arguments) provided as in a call to emmeans.

If the specifications in ... would result in a list (i.e., an emm_list object), then by default, only the last element of that list is passed to glht. However, if ... contains a which argument consisting of integer values, the list elements with those indexes are selected and combined and passed on to glht. No checking is done on whether the indexes are valid, and the keyword which must be spelled-out.

Details for as.glht

When no by variable is in force, we obtain a glht object; otherwise it is a glht_list. The latter is defined in emmeans, not multcomp, and is simply a list of glht objects. Appropriate convenience methods coef, confint, plot, summary, and vcov are provided, which simply apply the corresponding glht methods to each member.

Note

The multivariate-t routines used by glht require that all estimates in the family have the same integer degrees of freedom. In cases where that is not true, a message is displayed that shows what df is used. The user may override this via the df argument.

Examples

if(require(multcomp, quietly = TRUE)) 
    emm_example("glht-multcomp") 
    # Use emm_example("glht-multcomp", list = TRUE) # to see just the code
    

emmeans documentation built on Oct. 18, 2023, 1:13 a.m.