ratebystate: Method for investigating the rate of one trait as a function of the state of another
Description
This function attempts to ask if the rate of a continuous character, y
, depends on the state of a separate continuous trait, x
. This is accomplished by regressing the squared contrasts in y
on the branch or node ancestral estimates of x
.Usage
ratebystate(tree, x, y, nsim=100, corr=c("pearson","spearman"), ...)
Arguments
x
a continuous character - the dependent variable in the model.
y
a second continuous trait - the response variable.
nsim
number of simulations for hypothesis testing.
corr
correlation method to use. Same as in cor
. ...
optional arguments which include sim.method
("fastBM"
or "sim.corrs"
; see fastBM
and sim.corrs
); method
Value
- This function returns a list with up to the following four elements:
- betavalue of the regression coefficient for square of the contrasts in
y
regressed on the ancestral or branch-wise estimated states for x
. - rcorrelation coefficient for
corr=corr
. - corrstring giving the value of
corr
. - methodstring giving the value of
method
.