smacofIndDiff {smacof} | R Documentation |
Performs smacof for individual differences also known as Three-Way smacof on a list of dissimilarity matrices. Various restrictions decompositions and restrictions on the weight matrix are provided.
smacofIndDiff(delta, ndim = 2, weightmat = NULL, init = NULL, metric = TRUE, ties = "primary", constraint = NULL, verbose = FALSE, modulus = 1, itmax = 1000, eps = 1e-6)
delta |
A list of dissimilarity matrices or a list objects of class dist |
ndim |
Number of dimensions |
weightmat |
Optional matrix with dissimilarity weights |
init |
Matrix with starting values for configurations (optional) |
metric |
If FALSE non-metric MDS is performed |
ties |
Tie specification for non-metric MDS |
constraint |
Either NULL , "idioscal" , "diagonal" , or "identity" (see details) |
verbose |
If TRUE , intermediate stress is printed out |
modulus |
Number of smacof iterations per monotone regression call |
itmax |
Maximum number of iterations |
eps |
Convergence criterion |
If the constraint is NULL
, INDSCAL is performed with identity configuration weight matrices.
An additional restriction can be imposed with "identity"
which restricts the configurations across individuals/replications/ways to be equal.
More unrestricted models are "diagonal"
which restricts only the configuration weight matrices to be diagonal and "idioscal"
is unrestricted.
obsdiss |
List of observed dissimilarities, normalized |
confdiss |
List of configuration dissimilarities |
conf |
List of matrices of final configurations |
gspace |
Joint configurations aka group stimulus space |
cweights |
Configuration weights |
stress.m |
stress value for metric MDS |
stress.nm |
stress value for non-metric MDS (if computed) |
stress.co |
Constrained stress value |
ndim |
Number of dimensions |
model |
Type of smacof model |
niter |
Number of iterations |
nobj |
Number of objects |
Jan de Leeuw and Patrick Mair
de Leeuw, J. & Mair, P. (2008). Multidimensional scaling using majorization: The R package smacof.
smacofConstraint
, smacofSym
, smacofRect
, smacofSphere.primal
, smacofSphere.dual
data(perception) res <- smacofIndDiff(perception) res summary(res) res.id <- smacofIndDiff(perception, constraint = "identity") res.diag <- smacofIndDiff(perception, constraint = "diagonal") res.idio <- smacofIndDiff(perception, constraint = "idioscal")