clara.object: Clustering Large Applications (CLARA) Object
Description
The objects of class "clara"
represent a partitioning of a large
dataset into clusters.Value
- A legitimate
clara
object is a list with the following components: - samplelabels or case numbers of the observations in the best sample, that is,
the sample used by the
clara
algorithm for the final partition. - medoidsthe medoids or representative objects of the clusters.
It is a matrix with in each row the coordinates of one medoid.
- clusteringthe clustering vector. A vector with length equal to the number of
observations, giving the number of the cluster to which each observation
belongs.
- objectivethe objective function for the final clustering of the entire dataset.
- clusinfomatrix, each row gives numeric information for one cluster. These are
the cardinality of the cluster (number of observations), and the maximal and
average dissimilarity between the observations in the cluster and the cluster's
medoid. The last column is the maximal dissimilarity
between the observations in the cluster and the cluster's medoid, divided by
the minimal dissimilarity between the cluster's medoid and the medoid of
any other cluster. If this ratio is small, the cluster is well-separated
from the other clusters.
- silinfolist with all information necessary to construct a silhouette plot of the
clustering of the best sample. This list is only available when 1 < k < n.
The first component is a matrix, with for each observation i in the best
sample, the cluster to which i belongs,
as well as the neighbor cluster of i (the cluster, not containing
i, for which the average dissimilarity between its observations and i is
minimal), and the silhouette width of i.
The other two components give the average silhouette width per cluster and
the average silhouette width for the best sample.
See
plot.partition
for more information. - dissan object of class
"dissimilarity"
, representing the total dissimilarity
matrix of the dataset. - dataa matrix containing the original or standardized measurements, depending
on the
stand
option of the function clara
.
GENERATION
This class of objects is returned from clara
.METHODS
The "clara"
class has methods for the following generic functions:
print
, summary
.INHERITANCE
The class "clara"
inherits from "partition"
.
Therefore, the generic functions plot
and clusplot
can
be used on a clara
object.