extract {DImodels}

Extract terms from a DI or autoDI model object

Description

Extracts terms from a DI or autoDI model object that were calculated using the data preparation functions prior to the model fitting procedure.

Usage

extract(obj, what = c("FULL","ADD","FG","AV","E"))
## S3 method for class 'DI'
extract(obj, what = c("FULL","ADD","FG","AV","E"))
## S3 method for class 'autoDI'
extract(obj, what = c("FULL","ADD","FG","AV","E"))

Arguments

obj

a DI or autoDI model object

what

the variable(s) to be extracted from the object.

Value

A list containing one or more of the following elements:

E

the evenness interaction variable

AV

the average pairwise interaction variable

FG

the functional group-related interaction variables

ADD

the additive species contributions interaction variables

FULL

all pairwise interactions

Author(s)

Rafael A. Moral, John Connolly and Caroline Brophy

References

Connolly J, T Bell, T Bolger, C Brophy, T Carnus, JA Finn, L Kirwan, F Isbell, J Levine, A Lüscher, V Picasso, C Roscher, MT Sebastia, M Suter and A Weigelt (2013) An improved model to predict the effects of changing biodiversity levels on ecosystem function. Journal of Ecology, 101, 344-355.

Kirwan L, J Connolly, JA Finn, C Brophy, A Lüscher, D Nyfeler and MT Sebastia (2009) Diversity-interaction modelling - estimating contributions of species identities and interactions to ecosystem function. Ecology, 90, 2032-2038.

See Also

DI

Examples

## Load the Switzerland data
  data(Switzerland)

## Fit the FG DImodel, with factors density and treatment, and with theta = 1
  m1 <- DI(y = "yield", density = "density", prop = 4:7, treat = "nitrogen", 
           FG = c("G","G","L","L"), DImodel = "FG", data = Switzerland)

## Extract the FG terms
  extract(m1, what = "FG")