Displaying 1 result from an estimated 1 matches for "dry_weight".
2008 Feb 25
0
Extracting variance components from a Manova
...timates of the variance components based on the sums
of squares from summary.manova()$SS is leading to an unacceptably large
bias. It is clear we need to use a better method (ReML?) to estimate the
covariance matrices!
The code we use for running the manova:
Y <- cbind(Pupal_Mass, Dev_Time, Dry_Weight, Rel_Fitness)
sire <- factor(Sire)
dam<- factor(Dam)
fit <- manova(Y ~ sire + dam:sire)
sireSS <- summary(fit)$SS$sire
etc.
the sire covariance matrix = (MS(sires) ? MS(dams)/(offspring/sire)
which gives us the correct answer with balanced data, but of course not
with unbalanced data....