| varCompPhylip {ape} | R Documentation |
Variance Components with Orthonormal Contrasts
Description
This function calls Phylip's contrast program and returns the phylogenetic and phenotypic variance-covariance components for one or several traits. There can be several observations per species.
Usage
varCompPhylip(x, phy, exec = NULL)
Arguments
x |
a numeric vector, a matrix (or data frame), or a list. |
phy |
an object of class |
exec |
a character string giving the name of the executable contrast program (see details). |
Details
The data x can be in several forms: (i) a numeric vector if
there is single trait and one observation per species; (ii) a
matrix or data frame if there are several traits (as columns) and a
single observation of each trait for each species; (iii) a list of
vectors if there is a single trait and several observations per
species; (iv) a list of matrices or data frames: same than (ii) but
with several traits and the rows are individuals.
If x has names, its values are matched to the tip labels of
phy, otherwise its values are taken to be in the same order
than the tip labels of phy.
Phylip (version 3.68 or higher) must be accessible on your computer. If
you have a Unix-like operating system, the executable name is assumed
to be "phylip contrast" (as in Debian); otherwise it is set
to "contrast". If this doesn't suit your system, use the
option exec accordingly. If the executable is not in the path, you
may need to specify it, e.g., exec = "C:/Program Files/Phylip/contrast".
Value
a list with elements varA and varE with the phylogenetic
(additive) and phenotypic (environmental) variance-covariance
matrices. If a single trait is analyzed, these contains its variances.
Author(s)
Emmanuel Paradis
References
Felsenstein, J. (2004) Phylip (Phylogeny Inference Package) version 3.68. Department of Genetics, University of Washington, Seattle, USA. http://evolution.genetics.washington.edu/phylip/phylip.html.
Felsenstein, J. (2008) Comparative methods with sampling error and within-species variation: Contrasts revisited and revised. American Naturalist, 171, 713–725.
See Also
Examples
## Not run:
tr <- rcoal(30)
### Five traits, one observation per species:
x <- replicate(5, rTraitCont(tr, sigma = 1))
varCompPhylip(x, tr) # varE is small
x <- replicate(5, rnorm(30))
varCompPhylip(x, tr) # varE is large
### Five traits, ten observations per species:
x <- replicate(30, replicate(5, rnorm(10)), simplify = FALSE)
varCompPhylip(x, tr)
## End(Not run)