R: MANCOVA

mancova {jmv} | R Documentation

## MANCOVA

### Description

Multivariate Analysis of Covariance

### Usage

    mancova(data, deps, factors = NULL, covs = NULL, multivar = list("pillai",
      "wilks", "hotel", "roy"), boxM = FALSE, shapiro = FALSE, qqPlot = FALSE)

### Arguments

`data` | the data as a data frame
`deps` | a string naming the dependent variable from `data`, variable must be numeric
`factors` | a vector of strings naming the factors from `data`
`covs` | a vector of strings naming the covariates from `data`
`multivar` | one or more of `'pillai'`, `'wilks'`, `'hotel'`, or `'roy'`; use Pillai's Trace, Wilks' Lambda, Hotelling's Trace, and Roy's Largest Root multivariate statistics, respectively
`boxM` | `TRUE` or `FALSE` (default), provide Box's M test
`shapiro` | `TRUE` or `FALSE` (default), provide Shapiro-Wilk test
`qqPlot` | `TRUE` or `FALSE` (default), provide a Q-Q plot of multivariate normality

### Value

A results object containing:

`results$multivar` |  |  |  |  | a table
`results$univar` |  |  |  |  | a table
`results$assump$boxM` |  |  |  |  | a table
`results$assump$shapiro` |  |  |  |  | a table
`results$assump$qqPlot` |  |  |  |  | an image

Tables can be converted to data frames with `asDF` or `as.data.frame`. For example:

`results$multivar$asDF`

`as.data.frame(results$multivar)`

### Examples

    data('iris')

    mancova(data = iris,
        deps = c('Sepal.Length', 'Sepal.Width', 'Petal.Length', 'Petal.Width'),
        factors = 'Species')

    #
    #  MANCOVA
    #
    #  Multivariate Tests
    #  ---------------------------------------------------------------------------
    #                                     value     F       df1    df2    p
    #  ---------------------------------------------------------------------------
    #    Species    Pillai's Trace          1.19    53.5      8    290    < .001
    #               Wilks' Lambda         0.0234     199      8    288    < .001
    #               Hotelling's Trace       32.5     581      8    286    < .001
    #               Roy's Largest Root      32.2    1167      4    145    < .001
    #  ---------------------------------------------------------------------------
    #
    #
    #  Univariate Tests
    #  -----------------------------------------------------------------------------------------------
    #                 Dependent Variable    Sum of Squares    df     Mean Square    F         p
    #  -----------------------------------------------------------------------------------------------
    #    Species      Sepal.Length                   63.21      2        31.6061     119.3    < .001
    #                 Sepal.Width                    11.34      2         5.6725      49.2    < .001
    #                 Petal.Length                  437.10      2       218.5514    1180.2    < .001
    #                 Petal.Width                    80.41      2        40.2067     960.0    < .001
    #    Residuals    Sepal.Length                   38.96    147         0.2650
    #                 Sepal.Width                    16.96    147         0.1154
    #                 Petal.Length                   27.22    147         0.1852
    #                 Petal.Width                     6.16    147         0.0419
    #  -----------------------------------------------------------------------------------------------
    #

[Package jmv version 0.8.6.2 Index]