Does Matlab provide any facility for evaluating clustering methods? (cluster compactness and cluster separation. ....) Or is there any toolbox for it?
Not in Matlab, but ELKI (Java) provides a dozen or so cluster quality measures for evaluation.
Matlab provides Silhouette index and there is a toolbox CVAP: Cluster Validity Analysis Platform for Matlab. Which includes following validity indexes:
- Davies-Bouldin
- Calinski-Harabasz
- Dunn index
- R-squared index
- Hubert-Levin (C-index)
- Krzanowski-Lai index
- Hartigan index
- Root-mean-square standard deviation (RMSSTD) index
- Semi-partial R-squared (SPR) index
- Distance between two clusters (CD) index
- weighted inter-intra index
- Homogeneity index
- Separation index
Note that you might need precompiled LIBRA binaries for your platform.
You can try Silhouette plot from the Statistical toolbox.
For an example see this documentation.
Be aware that the Silhouette in Matlab has some strange behavior for singleton clusters. It assigns a score of 1 for singletons, when, for me, a more reasonable approach would be to give 0 for these clusters. In the Matlab implementation, if you give number of clusters as number of objects, Silhouette will give you a score of 1.
来源：https://stackoverflow.com/questions/10365616/cluster-quality-measures