InfDim (version 1.0)

IDM: Infinite-dimensional model (IDM)

Description

A function to calculate infinite-dimensional model (IDM) elements as implemented by Kirkpatrick et al. (1990).

Usage

IDM(P, age)

Arguments

P

Covariance matrix for sizes-at-ages.

age

A numeric vector of ages at which sizes were measured. Ages must be positive valuies given in an ascending order.

Value

Details

The IDM model detects alternative patterns of growth (i.e. shapes of the growth trajectory) present in a population, as well as the amounts of phenotypic variation accounted for by each of the growth patterns, by decomposing a covariance matrix of size over a set of ages. For further detailes about the model formualtion and its use, see Kirkpatrick et al. (1990) and Kuparinen and Bjrklund (in press).

References

Kirkpatrick M, Lofsvold D, Bulmer M (1990) Analysis of the inheritance, selection and evolution of growth trajectories. Genetics 124:979-993.

Kuparinen A, Bjrklund M (2011) Theory put into practice: an R implementation of the infinite-dimensional model. Ecological Modelling (in press).

See Also

IDM.bootCI.

Examples

#This example utilizes data given in Kirkpatrick et al. (1990). 
myage=c(2,3,4)
myP=matrix(c(436.0,522.3,424.2,522.3,808.0,664.7,424.2,664.7,558.0),nrow=3,ncol=3,byrow=TRUE)

out=IDM(P=myP,age=myage)

#Growth patterns (i.e. trajectories) 
out$Trajectories

#Proportions of variation accounted for by each growth trajectory
out$Percent.trajectory