Introduction to Pattern Recognition: A Matlab Approach

198 CHAPTER 7 Clustering

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FIGURE 7.10

Clustering resulting from application of the spectral clustering algorithm on data set X

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in Example 7.6.2 when

(a) e = 1.5 and (b) e = 3. Points assigned in the same cluster are denoted by the same symbol. Observe the

sensitivity in the choice of parameters.

Plot the clustering results (see Figure 7.10(a)), typing

figure(2),plot(X10(1,bel==0),X10(2,bel==0),'ro',...

X10(1,bel==1),X10(2,bel==1),'b*')

figure(2), axis equal

Step 3. Work as in step 2, setting e equal to 3 (Figure 7.10(b)). Comparing Figures 7.10(a) and 7.10(b),

note the influence of the parameter values ...