stop_powersammon: STOPS version of sammon with powers

In stops: Structure Optimized Proximity Scaling

STOPS version of sammon with powers

Description

This is power stress with free kappa and lambda but rho is fixed to -1 and the weights are delta.

Usage

stop_powersammon(
  dis,
  theta = c(1, 1),
  type = "ratio",
  weightmat = NULL,
  init = NULL,
  ndim = 2,
  itmaxi = 10000,
  acc = 1e-08,
  ...,
  stressweight = 1,
  structures = c("cclusteredness", "clinearity", "cdependence", "cmanifoldness",
    "cassociation", "cnonmonotonicity", "cfunctionality", "ccomplexity", "cfaithfulness",
    "cregularity", "chierarchy", "cconvexity", "cstriatedness", "coutlying",
    "cskinniness", "csparsity", "cstringiness", "cclumpiness", "cinequality"),
  strucweight = rep(1/length(structures), length(structures)),
  strucpars,
  verbose = 0,
  stoptype = c("additive", "multiplicative"),
  registry = struc_reg
)

Arguments

dis	numeric matrix or dist object of a matrix of proximities
theta	the theta vector of powers; a vector of length two where the first element is kappa (for the fitted distances), the second lambda (for the observed proximities). If a scalar is given it is recycled for the free parameters. Defaults to 1 1.
type	MDS type. Defaults to "ratio".
weightmat	(optional) a matrix of nonnegative weights
init	(optional) initial configuration
ndim	number of dimensions of the target space
itmaxi	maximum number of iterations
acc	accuracy (defaults to 1e-8)
...	additional arguments to be passed to the fitting procedure
stressweight	weight to be used for the fit measure; defaults to 1
structures	which structures to look for
strucweight	weight to be used for the structures; defaults to 0.5
strucpars	a list of parameters for the structuredness indices; each list element corresponds to one index in the order of the appeacrance in structures
verbose	numeric value hat prints information on the fitting process; >2 is extremely verbose
stoptype	which weighting to be used in the multi-objective optimization? Either 'additive' (default) or 'multiplicative'.
registry	registry object with c-structuredness indices.

Value

A list with the components

• stress: the stress

• stress.m: default normalized stress

• stoploss: the weighted loss value

• struc: the structuredness indices

• parameters: the parameters used for fitting (kappa, lambda)

• fit: the returned object of the fitting procedure

• stopobj: the stopobj object

stops documentation built on July 7, 2025, 3:01 p.m.