Information Technology Reference
In-Depth Information
Table 2.7
IFCM parameters
Parameters
Explanation
f
The input file name
c
The number of clusters, the default value is 3
m
The fuzzy factor, the default value is 2
w
The type of the sample weights, 0-equal (default), 1-user specified
s
The type of the initial centroids, 0-random (default), 1-user specified
i
The maximal number of iterations until convergence, the default value is 100
t
The threshold for stopping the iterations, the default value is 0.001
Table 2.8 Descriptions of two cluster validity criteria
Validity criteria
Functional description
Optimal cluster number
p
j = 1 u ij
i = 1
c
1
p
Partition coefficient
V PC
=
argmax c
(
V PC
,
U
,
c
)
i = 1
c
j = 1 u ij log u ij
p
1
p
Classification entropy
V CE =−
argmin c ( V CE , U , c )
where p is the number of samples in the data set, and c is the number of clusters
Step 2 Calculate the membership degrees and the centroids iteratively. First,
according to Eq. ( 2.154 ), we have
0
.
401 0
.
317 0
.
281
0
.
215 0
.
252 0
.
533
0
.
289 0
.
231 0
.
480
0
.
896 0
.
054 0
.
051
0
.
166 0
.
631 0
.
203
U
(
0
) =
0
.
319 0
.
390 0
.
291
0
.
179 0
.
213 0
.
607
0
.
000 0
.
000 1
.
000
1
.
000 0
.
000 0
.
000
0
.
000 1
.
000 0
.
000
Step 3 According to Eq. ( 2.155 ), update the centroids as follows:
.
,
.
.
,
.
.
,
.
0
365
0
382
0
838
0
084
0
782
0
153
.
,
.
.
,
.
.
,
.
V
(
1
) =
0
762
0
151
0
677
0
136
0
586
0
258
0
.
678
,
0
.
211
0
.
574
,
0
.
206
0
.
666
,
0
.
165
0
.
625
,
0
.
182
0
.
207
,
0
.
700
0
.
190
,
0
.
737
0
.
488
,
0
.
203
0
.
707
,
0
.
221
0
.
509
,
0
.
457
0
.
361
,
0
.
516
0
.
369
,
0
.
561
0
.
667
,
0
.
130
 
Search WWH ::




Custom Search