Curve-ergmTerm-a37fe1f0: Impose a curved structure on term parameters
In ergm: Fit, Simulate and Diagnose Exponential-Family Models for Networks

Curve-ergmTerm

R Documentation

Impose a curved structure on term parameters

Description

Arguments may have the same forms as in the API, but for convenience, alternative forms are accepted.

If the model in formula is curved, then the outputs of this operator term's map argument will be used as inputs to the curved terms of the formula model.

Curve is an obsolete alias and may be deprecated and removed in a future release.

Usage

# binary: Curve(formula, params, map, gradient=NULL, minpar=-Inf, maxpar=+Inf, cov=NULL)

# binary: Parametrise(formula, params, map, gradient=NULL, minpar=-Inf, maxpar=+Inf,
#           cov=NULL)

# binary: Parametrize(formula, params, map, gradient=NULL, minpar=-Inf, maxpar=+Inf,
#           cov=NULL)

# valued: Curve(formula, params, map, gradient=NULL, minpar=-Inf, maxpar=+Inf, cov=NULL)

# valued: Parametrise(formula, params, map, gradient=NULL, minpar=-Inf, maxpar=+Inf,
#           cov=NULL)

# valued: Parametrize(formula, params, map, gradient=NULL, minpar=-Inf, maxpar=+Inf,
#           cov=NULL)

Arguments

`formula`	a one-sided `ergm()`-style formula with the terms to be evaluated
`params`	a named list whose names are the curved parameter names, may also be a character vector with names.
`map`	the mapping from curved to canonical. May have the following forms: a `⁠function(x, n, ...)⁠` treated as in the API: called with `x` set to the curved parameter vector, `n` to the length of output expected, and `cov` , if present, passed in `...` . The function must return a numeric vector of length `n` . a numeric vector to fix the output coefficients, like in an offset. a character string to select (partially-matched) one of predefined forms. Currently, the defined forms include: `"rep"` recycle the input vector to the length of the output vector as a `rep` function would.
`gradient`	its gradient function. It is optional if `map` is constant or one of the predefined forms; otherwise it must have one of the following forms: a `⁠function(x, n, ...)⁠` treated as in the API: called with `x` set to the curved parameter vector, `n` to the length of output expected, and `cov` , if present, passed in `...` . The function must return a numeric matrix with `length(params)` rows and `n` columns. a numeric matrix to fix the gradient; this is useful when map is linear. a character string to select (partially-matched) one of predefined forms. Currently, the defined forms include: `"linear"` calculate the (constant) gradient matrix using finite differences. Note that this will be done only once at the initialization stage, so use only if you are certain `map` is, in fact, linear.
`minpar`, `maxpar`	the minimum and maximum allowed curved parameter values. The parameters will be recycled to the appropriate length.
`cov`	optional