This function computes the Swofford--Olsen--Waddell--Hillis (SOWH) test, a parametric bootstrap test. The function is computational very demanding and likely to be very slow.
Usage
SOWH.test(x, n = 100, restricted = list(optNni = FALSE), optNni = TRUE,
trace = 1, ...)Arguments
- x
an object of class
"pml".- n
the number of bootstrap replicates.
- restricted
list of restricted parameter settings.
- optNni
Logical value indicating whether topology gets optimized (NNI).
- trace
Show output during computations.
- ...
Further arguments passed to
"optim.pml".
Value
an object of class SOWH. That is a list with three elements, one is a matrix containing for each bootstrap replicate the (log-) likelihood of the restricted and unrestricted estimate and two pml objects of the restricted and unrestricted model.
Details
SOWH.test performs a parametric bootstrap test to compare two trees.
It makes extensive use simSeq and optim.pml and can take quite
long.
References
Goldman, N., Anderson, J. P., and Rodrigo, A. G. (2000) Likelihood -based tests of topologies in phylogenetics. Systematic Biology 49 652-670.
Swofford, D.L., Olsen, G.J., Waddell, P.J. and Hillis, D.M. (1996) Phylogenetic Inference in Hillis, D.M., Moritz, C. and Mable, B.K. (Eds.) Molecular Systematics (2nd ed.) 407-514, Sunderland, MA: Sinauer
Author
Klaus Schliep klaus.schliep@gmail.com
Examples
# in real analysis use larger n, e.g. 500 preferably more
if (FALSE) {
data(Laurasiatherian)
dm <- dist.logDet(Laurasiatherian)
tree <- NJ(dm)
fit <- pml(tree, Laurasiatherian)
fit <- optim.pml(fit, TRUE)
set.seed(6)
tree <- rNNI(fit$tree, 1)
fit <- update(fit, tree = tree)
(res <- SOWH.test(fit, n=100))
summary(res)
}