getDF function

Extract Degrees of Freedom from Linear Hypotheses of Fixed Effects or LS Means

Determine degrees of freedom for custom linear hypotheses of fixed effects or LS Means using one of three possible approximation methods.

getDF(obj, L, method = c("contain", "residual", "satterthwaite"), ...)

Arguments

• obj: (VCA) object
• L: (matrix) specifying one or multiple linear hypothese, as returned by function getL
• method: (character) the method to be used to determine the degrees of freedom for a linear hypothesis
• ...: additional parameters

Returns

(numeric) vector with the DFs for each row of 'L'

Details

This is a convenience function to determine the DFs for linear hypotheses in the same way as function test.fixef. Only the "DF" part is returned here which can be passed to other functions expecting DFs as input.

Examples

## Not run:

data(VCAdata1)
tmpDat <- VCAdata1[VCAdata1$sample==1,]
tmpDat <- tmpDat[-c(11,51,73:76),]
fitMM <- anovaMM(y~(lot+device)/(day)/(run), tmpDat)
fitMM
L <- getL(fitMM, c("lot1-lot2", "device1-device2"))
getDF(fitMM, L)                                         # method="contain" is Default
getDF(fitMM, L, method="res")

getDF(fitMM, L, method="satt")          # takes quite long for this model
## End(Not run)

Author(s)

Andre Schuetzenmeister andre.schuetzenmeister@roche.com