NEWS | R Documentation |
Aspect ratio 1 added as default for the bubble plot option in plot.smacof()
.
Function dissWeight added to create weights as a function of the dissimilarities. Removed dissimilarities with weights 0 from Shepard plot. multistart.smacof added.
In mds, smacofSym, smacofConstraint, smacofIndDiff, and smacofSphere the order of computations in update changed. This update improves the speed of computations for large data when using weightmat.
Hue change in jackknife plot.
Some fixes in the permutation tests.
Permutation tests based on permutations of the original data matrix added.
biplot
function for creating MDS biplots added.
Optimization in smacofConstraint
improved (monotone regression in two directions).
Some plot cosmetics for smacofIndDiff
and Procrustes
calls.
Transformations in smacofIndDiff
use C implementation (mspline can be done as well).
Drift vector model added.
Datasets added.
smacofConstraint
allows now for data frame and matrices for external variables, sanity checks added.
Verbose output now says "stress (raw)".
init default argument is now "torgerson"
(before it was NULL
which used Torgerson scaling anyway).
Bug for optimal scaling on external variables in smacofConstraint
removed.
SPP-plot for unfolding models fixed.
Some datasets added.
Stress-per-point (spp) is now returned as percentage stress contribution including the squared error matrix (resmat
).
If there are missing input dissimilarities, the corresponding weight matrix is created automatically.
Sanity check for negative input dissimilarities.
Some plot cosmetrics.
Output value structure for dual algorithm in smacofSphere
changed, circle added in configuration plot.
Function randomstress
for computing (average) stress values based on random input dissimilarities.
Unidimensional scaling added (all permutations): uniscale
.
Procrustes added: Procrustes
including print and plot methods.
Function torgerson
(for classical scaling) is now exported.
Bug in smacofConstraint
for external missing values removed.
Bug in smacofIndDiff
with initial starting configurations fixed. Stress is now normalized to Stress-1.
Several wrapper functions added: mds
, unfolding
, indscal
, idioscal
.
Recoding of transformations:
Ordinal transformations are coded in C.
Added monotone spline transformations (type = mspline
with number of interior knots spline.intKnots
and degree of the spline spline.degree = 2
.
smacofConstraint
allows for transformations of the external variables through constraint.type
("ratio", "interval", "ordinal", "spline", "spline",
or "mspline"
). Missing values (NA
) are estimated by the model. Choosing the number of external variables equal to the number of dimensions together with constraint.type = "ordinal", constraint.ties = "primary"
will effectively restrict the configuration to parallel regions defined by the categories of the external variables.
Stress values reported by verbose = TRUE
during iterations of smacofSym
, smacofConstraint
, and smacofRect
are normalized Stress values.
Gravity model for dissimilarity computation based on co-occurrences added: see gravity()
.
The circle
argument in smacofRect()
allows for circular restrictions on the configurations.
All smacof functions now return Stress-1 (before it was squared Stress-1); the value return by the function is now called stress
.
The metric
argument is deprecated. Now type
should be used (either "ordinal"
, "interval"
, or "ratio"
)
for pretty much all smacof functions.
smacofSphere.primal()
and smacofSphere.dual()
are now merged into a single function smacofSphere()
with a corresponding algorithm
argument.
smacofConstraint()
now returns weight matrix C
.
Plot updates:
For unfolding (smacofRect()
) configurations: joint = TRUE
as default.
Configuration plot looks a bit fancier now (labels and points as default), also aspect ratio = 1 as default.
A note in plot help file added that in the stress plot the SPP from a various smacof functions is rescaled to percentages (which sum up to 100).
Datasets:
Labels for rectangle dataset now provided in English.
Dataset on Republican statements added (document-term matrix).