Latent Variables
Generic function for the latent variables of a model.
latvar(object, ...)
lv(object, ...)object |
An object for which the extraction of latent variables is meaningful. |
... |
Other arguments fed into the specific
methods function of the model. Sometimes they are fed
into the methods function for |
Latent variables occur in reduced-rank regression models, as well as in quadratic and additive ordination models. For the latter two, latent variable values are often called site scores by ecologists. Latent variables are linear combinations of the explanatory variables.
The value returned depends specifically on the methods function invoked.
Thomas W. Yee
Yee, T. W. and Hastie, T. J. (2003). Reduced-rank vector generalized linear models. Statistical Modelling, 3, 15–41.
Yee, T. W. (2004). A new technique for maximum-likelihood canonical Gaussian ordination. Ecological Monographs, 74, 685–701.
Yee, T. W. (2006). Constrained additive ordination. Ecology, 87, 203–213.
latvar.qrrvglm,
latvar.rrvglm,
latvar.cao,
lvplot.
## Not run:
hspider[, 1:6] <- scale(hspider[, 1:6]) # Standardized environmental vars
set.seed(123)
p1 <- cao(cbind(Pardlugu, Pardmont, Pardnigr, Pardpull, Zoraspin) ~
WaterCon + BareSand + FallTwig + CoveMoss + CoveHerb + ReflLux,
family = poissonff, data = hspider, Rank = 1, df1.nl =
c(Zoraspin = 2.5, 3), Bestof = 3, Crow1positive = TRUE)
var(latvar(p1)) # Scaled to unit variance # Scaled to unit variance
c(latvar(p1)) # Estimated site scores
## End(Not run)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.