Para: Curve parameters of eHOF models

In eHOF: Extended HOF (Huisman-Olff-Fresco) Models

Curve parameters of eHOF models

Description

Derive common shape parameters from the different model types. Calculate a set of parameters (see values below) from eHOF models.

Usage

## S3 method for class 'HOF'
Para(resp, model, newdata = NULL, ...)
## S3 method for class 'HOF.list'
Para(resp, ...)

Arguments

resp	response model results, see HOF.
model	response model type. If not specified, the output of pick.model will be used.
newdata	new gradient vector.
...	further arguments passed to or from other methods, e.g. for pick.model.

Details

For models VI and VII Para will give you two expectancy values for the ranges left and right of the pessimum between the model optima. If you want to have the overall expectancy value, use: gradient <- seq(min(Para(resp)$range), max(Para(resp)$range), length.out=10000) weighted.mean(gradient, predict(resp, newdata=gradient))

Value

species	Name or abbreviat of the species.
abund sum	Abundance sum, i.e. sum of all response values divided by M.
range	Range of x values.
model	Model type, if not specified the result of pick.model.
para	Model parameters (a to d).
M	Maximum response value, specified in the HOF function call.
mini	Location of the minimum, i.e. the gradient value, where the response is lowest, for model VI and VII the lowest response between the two optima.
pess	Lowest estimated response value.
top	Highest estimated response value(s).
opt	Location of the optimum, i.e. the gradient value, where the species response is highest. NA for model I and an optimum interval for model type III.
expect	Expectancy value, i.e. average x value under the model curve).
max slope	Highest slope, i.e. maximum of the first derivation of the curve.
centralBorder	Following Heegard, the central borders are calculated as the gradient values, where the response reaches "exp(-1/2)" of the top.
outerBorder	Following Heegard, the outer borders of the species niche are calculated as the gradient values, where the response reaches exp(-2) of the top.
raw mean	Average of measured x values.

Author(s)

Florian Jansen

References

Heegard, E. (2002) The outer border and central border for species-environmental relationships estimated by non-parametric generalised additive models. Ecological Modelling, 157, 131-139. Damgaard, C. (2006) Modelling ecological presence-absence data along an environmental gradient: threshold levels of the environment. Environ Ecol Stat 13:229-236.

eHOF documentation built on April 23, 2022, 1:05 a.m.