mrds: create.ddfobj – R documentation

Become an expert in R — Interactive courses, Cheat Sheets, certificates and more!

create.ddfobj

Create detection function object

Description

Creates and populates a specific list structure to define a detection function object and its data. The ddfobj is used throughout the package as a calling argument to various functions.

Usage

create.ddfobj(model, xmat, meta.data, initial)

Arguments

`model`	model list with key function and possibly adjustment functions, scale formula, and shape formula
`xmat`	model data frame
`meta.data`	list of options describing data like width, etc
`initial`	named list of initial values for parameters of the detection function (should have at least `"scale"`, maybe also have `"shape"` and `"adjustments"`)

Value

Distance sampling function object list with elements that all can be null except type:

`type`	type of detection function hn, hr, gamma, unif, logistic
`xmat`	model data frame
`intercept.only`	TRUE if scale = ~1 and any shape formula =~1
`scale`	sublist with elements (can be NULL i.e., unif key):formula, parameters, design matrix (dm)
`shape`	sublist with elements (power of hazard rate or gamma) (can be NULL i.e., unif or hn key):formula, parameters, design matrix (dm)
`adjustment`	sublist with elements (is NULL if no adjustments used):series,order,scale,parameters
`g0`	sublist with elements (not used at present):formula,parameters, design matrix(dm), link

Note

Internal function not meant to be called by user

Author(s)

Jeff Laake