ic.sigma {geiger} | R Documentation |
Uses independent contrasts to estimate the evolutionary variance-covariance matrix for n quantitative characters.
ic.sigma(phy, data, data.names=NULL)
phy |
Phylogenetic tree in 'phylo' format |
data |
Data matrix |
data.names |
Tip names for data vector that match tree species; ignored if data includes names |
Data for this function should be a matrix of continuously-valued variables.
Returns the estimated evolutionary variance-covariance matrix of the variables under a multivariate Brownian motion model. If you have n characters in your analysis, this will be an nxn matrix. Diagonal elements represent rate estimates for individual characters, while off-diagonal elements represent the estimated covariance between two characters.
Luke J. Harmon
Revell, L. J., L. J. Harmon, R. B. Langerhans, and J. J. Kolbe. 2007. A phylogenetic approach to determining the importance of constraint on phenotypic evolution in the neotropical lizard, Anolis cristatellus. Evolutionary Ecology Research 9: 261-282.
data(geospiza) attach(geospiza) ic.sigma(geospiza.tree, geospiza.data)