Compute vectors associated with 1-way ANOVA
Usage
vaov(x, ...)
# S3 method for class 'formula'
vaov(x, data = parent.frame(), ...)Value
A data frame with variables including grandMean,
groupMean, ObsVsGrand, STotal, ObsVsGroup,
SError, GroupVsGrand, and STreatment. The usual SS
terms can be computed from these by summing.
Details
This is primarily designed for demonstration purposes to show how 1-way ANOVA models partition variance. It may not work properly for more complicated models.
Examples
aov(pollution ~ location, data = AirPollution)
#> Call:
#> aov(formula = pollution ~ location, data = AirPollution)
#>
#> Terms:
#> location Residuals
#> Sum of Squares 468 202
#> Deg. of Freedom 2 3
#>
#> Residual standard error: 8.205689
#> Estimated effects may be unbalanced
vaov(pollution ~ location, data = AirPollution)
#> location pollution GrandMean GroupMean ObsVsGrand STotal ObsVsGroup
#> 1 Hill Suburb 124 120 117 4 16 7
#> 2 Hill Suburb 110 120 117 -10 100 -7
#> 3 Plains Suburb 107 120 111 -13 169 -4
#> 4 Plains Suburb 115 120 111 -5 25 4
#> 5 Urban City 126 120 132 6 36 -6
#> 6 Urban City 138 120 132 18 324 6
#> SError GroupVsGrand STreatment
#> 1 49 -3 9
#> 2 49 -3 9
#> 3 16 -9 81
#> 4 16 -9 81
#> 5 36 12 144
#> 6 36 12 144