I'm trying to compute the Silhouette value of a clustering partition done with SOM method using the function intCriteria of the clusterCrit package but it returns me a Nan value: somebody knows why?
To simplify my case, here there is an example:
< test
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 37.28577 8.902218 17.93830 38.80381 6.825286 18.44061
[2,] 37.25598 8.693962 18.09256 38.81784 7.005092 18.17899
[3,] 37.54612 8.262074 18.07639 38.87837 6.592799 18.31604
[4,] 37.56661 8.651182 17.98653 38.76980 6.596529 18.46937
[5,] 37.59454 8.546921 17.93558 39.00177 6.508707 18.40102
[6,] 37.62195 8.422909 18.03132 38.86634 7.024104 18.30201
[7,] 37.19365 8.662608 18.01295 38.37456 7.173594 18.24273
[8,] 37.63161 8.495688 18.05909 38.92736 6.884675 18.44871
[9,] 37.30077 8.488438 18.02636 38.60844 7.004214 18.45600
[10,] 37.52518 8.610817 18.00498 38.57547 6.877532 18.36552
< datissimi = som(test, grid=somgrid(xdim=2, ydim=4,
topo='rectangular'), rlen=500, keep.data=T)
somissimo = datissimi$unit.classif
intCriteria(test, somissimo, "Silhouette")
$silhouette
[1] NaN
Thanks,
Paola