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Miscellaneous methods for emmGrid objects

Source: R/emmGrid-methods.R
emmGrid-methods.Rd

Miscellaneous methods for emmGrid objects

Usage

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

# S3 method for class 'emmGrid'
print(x, ..., export = FALSE)

# S3 method for class 'emmGrid'
vcov(object, ..., sep = get_emm_option("sep"))

Arguments

object

An emmGrid object

...

(required but not used)

x

An emmGrid object

export

Logical value. If FALSE, the object is printed. If TRUE, a list is invisibly returned, which contains character elements named summary and annotations that may be saved or displayed as the user sees fit. summary is a character matrix (or list of such matrices, if a by variable is in effect). annotations is a character vector of the annotations that would have been printed below the summary or summaries.

sep

separator for pasting levels in creating row and column names for vcov() results

Value

The vcov method returns a symmetric matrix of variances and covariances for predict.emmGrid(object, type = "lp")

Examples

warp.lm <- lm(breaks ~ wool * tension, data = warpbreaks)
warp.emm <- emmeans(warp.lm, ~ tension | wool)
vcov(warp.emm) |> zapsmall()
#>          L A      M A      H A      L B      M B      H B
#> L A 13.29887  0.00000  0.00000  0.00000  0.00000  0.00000
#> M A  0.00000 13.29887  0.00000  0.00000  0.00000  0.00000
#> H A  0.00000  0.00000 13.29887  0.00000  0.00000  0.00000
#> L B  0.00000  0.00000  0.00000 13.29887  0.00000  0.00000
#> M B  0.00000  0.00000  0.00000  0.00000 13.29887  0.00000
#> H B  0.00000  0.00000  0.00000  0.00000  0.00000 13.29887

vcov(pairs(warp.emm), sep = "|") |> zapsmall()
#>           L - M|A  L - H|A   M - H|A   L - M|B  L - H|B   M - H|B
#> L - M|A  26.59774 13.29887 -13.29887   0.00000  0.00000   0.00000
#> L - H|A  13.29887 26.59774  13.29887   0.00000  0.00000   0.00000
#> M - H|A -13.29887 13.29887  26.59774   0.00000  0.00000   0.00000
#> L - M|B   0.00000  0.00000   0.00000  26.59774 13.29887 -13.29887
#> L - H|B   0.00000  0.00000   0.00000  13.29887 26.59774  13.29887
#> M - H|B   0.00000  0.00000   0.00000 -13.29887 13.29887  26.59774