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162     CHAPTER 6 CLASSIFICATION FRAMEWORK OF fMRI DATA






              Table 6.6 Classification Accuracies in Percentage
                                 Logistic Regression                Support Vector Machine
                        Without            With             Without             With
              Subject   Standardization    Standardization  Standardization     Standardization
              04799     70                 65               69                  64
              04820     61                 66               65                  60
              04847     91                 94               91                  89
              05675     76                 76               76                  74
              05680     64                 59               64                  57
              05710     82                 81               85                  82
              Average   74                 74               75                  71





              Table 6.7 Classification Accuracies in Percentage
                                 Logistic Regression                Support Vector Machine
                        Without            With             Without             With
              Subject   Standardization    Standardization  Standardization     Standardization
              04799     88                 94               94                  94
              04820     94                 97               97                  97
              04847     93                 94               94                  94
              05675     90                 99               99                  99
              05680     84                 99               96                  97
              05710     91                 96               94                  94
              Average   90                 97               96                  96


             averaging-based feature selection discarded precious information. With standardization of data, the
             average accuracy was the same for LR but it decreased in SVM.

             6.3.5.4 N-most active-based feature
             In Table 6.7, the N-most active voxels were utilized for reducing the number of features in the feature
             vector. Table 6.7 presents the performance of the experiment where N-most active voxels were con-
             sidered. It can be seen that the accuracy increased compared to previous experiments and data stan-
             dardization increased accuracy in both cases.

             6.3.5.5 N-most active ROI-based feature
             This is similar to the above active method. Here, the N most active voxels were employed uniformly
             from seven ROIs. The performances are presented in Table 6.8. It can be seen that accuracies were less
             when compared with the previous N-most active based feature but it improved performance compared
             with others.
                In LR, the performance increased with standardization.
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