emmeans (version 1.7.0)

rbind.emmGrid: Combine or subset emmGrid objects

Description

These functions provide methods for rbind and [ that may be used to combine emmGrid objects together, or to extract a subset of cases. The primary reason for doing this would be to obtain multiplicity-adjusted results for smaller or larger families of tests or confidence intervals.

Usage

# S3 method for emmGrid
rbind(..., deparse.level = 1, adjust = "bonferroni")
# S3 method for emm_list
rbind(..., which, adjust = "bonferroni")
# S3 method for emmGrid
+(e1, e2)
# S3 method for emmGrid
[(x, i, adjust, drop.levels = TRUE, ...)
# S3 method for emmGrid
subset(x, subset, ...)
force_regular(object)

Arguments

...

Additional arguments: In rbind, object(s) of class emmGrid. In "[", it is ignored. In subset, it is passed to [.emmGrid]

deparse.level

(required but not used)

adjust

Character value passed to update.emmGrid

which

Integer vector of subset of elements to use; if missing, all are combined

e1

An emmGrid object

e2

Another emmGrid object

x

An emmGrid object to be subsetted

i

Integer vector of indexes

drop.levels

Logical value. If TRUE, the "levels" slot in the returned object is updated to hold only the predictor levels that actually occur

subset

logical expression indicating which rows of the grid to keep

object

an object of class emmGrid

Value

A revised object of class emmGrid

The rbind method for emm_list objects simply combines the emmGrid objects comprising the first element of ....

The result of e1 + e2 is the same as rbind(e1, e2)

force_regular adds extra (invisible) rows to an emmGrid object to make it a regular grid (all combinations of factors). This regular structure is needed by emmeans. An object can become irregular by, for example, subsetting rows, or by obtaining contrasts of a nested structure.

Examples

# NOT RUN {
warp.lm <- lm(breaks ~ wool * tension, data = warpbreaks)
warp.rg <- ref_grid(warp.lm)

# Do all pairwise comparisons within rows or within columns, 
# all considered as one faily of tests:
w.t <- pairs(emmeans(warp.rg, ~ wool | tension))
t.w <- pairs(emmeans(warp.rg, ~ tension | wool))
rbind(w.t, t.w, adjust = "mvt")
update(w.t + t.w, adjust = "fdr")  ## same as above except for adjustment

### Working with 'emm_list' objects
mod <- lm(conc ~ source + factor(percent), data = pigs)
all <- emmeans(mod, list(src = pairwise ~ source, pct = consec ~ percent))
rbind(all, which = c(2, 4), adjust = "mvt")

# Show only 3 of the 6 cases
summary(warp.rg[c(2, 4, 5)])

# After-the-fact 'at' specification
subset(warp.rg, wool == "A")  ## or warp.rg |> subset(wool == "A")


### Irregular object
tmp <- warp.rg[-1]
## emmeans(tmp, "tension")   # will fail because tmp is irregular
emmeans(force_regular(tmp), "tension")   # will show some results
# }