VCA: SattDF – R documentation

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SattDF

Satterthwaite Approximation for Total Degrees of Freedom and for Single Variance Components

Description

This function estimates degrees of freedom of the total variance (type="total") in random models or individual variance components (type="individual"). It bases on the results of the unified approach to ANOVA-type estimation of variance components as implemented in functions anovaVCA and anovaMM.

Usage

SattDF(MS, Ci, DF, type = c("total", "individual"))

Arguments

`MS`	(numeric) vector of sequential mean squares (ANOVA type-1).
`Ci`	(matrix) where elements are numeric values representing the inverse of the coefficient matrix for calculation of expected mean squares (see `anovaVCA`).
`DF`	(numeric) vector with the degrees of freedom for each factor in a ANOVA type-1 model.
`type`	(character) string specifying whether "total" degrees of freedom should be approximated or those of individual variance components

Details

Function is used internally, thus, it is not exported. Option 'type="total"' is used in functions anovaVCA and anovaMM for approximating total DF. Option 'type="individual"' is used in function VCAinference when choosing 'ci.method="satterthwaite"' for approximating DFs for individual variance components.

Value

numeric value representing the Satterthwaite DFs of the total variance.

Author(s)

Andre Schuetzenmeister andre.schuetzenmeister@roche.com

Examples

## Not run: 
data(dataEP05A2_2)
res <- anovaVCA(y~day/run, dataEP05A2_2)
VCA:::SattDF(res$aov.tab[-1,"MS"], getMat(res, "Ci.MS"), res$aov.tab[-1,"DF"], type="tot")

# now approximating individual DF for variance components
VCA:::SattDF(res$aov.tab[-1,"MS"], getMat(res, "Ci.MS"), res$aov.tab[-1,"DF"], type="i")

## End(Not run)

VCA

Variance Component Analysis

v1.4.3

GPL (>= 3)

Authors

Andre Schuetzenmeister [aut, cre], Florian Dufey [aut]

Initial release

2020-06-17