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4.6 RESULT AND ANALYSIS         67






                Table 4.4 Feature Dimension Reduced After Applying PCA
                                          40×             100×            200×            400×
                ResNet50                  650             659             658             622
                InceptionV3               511             521             507             487
                Inception ResnetV2        286             297             291             283
                Xception                  636             652             637             613


               4.5.3 CLASSIFICATION
               Classifiers: For classification purposes, three classifiers are used (LR, SVM, and K-NN). All these clas-
               sifiers are available in the scikit-learn package. The reduced image feature vectors are passed to the
               classifiers for classification. Every classifier is first trained on the training set and tested on the test set.




               4.5.4 TUNING HYPERPARAMETERS OF THE CLASSIFIERS
               Some of the parameters of the classifiers, such as for LR, the parameters C, for SVM the parameters C,
               and gamma both with rbf kernel and for K–NN the parameters n_neighbors are tuned.
                  To tune the hyperparameters, the 10-fold cross validation approach is used. For each of the clas-
               sifiers, 10-fold cross validation is performed on the training set with the combination of the above-
               mentioned hyperparameters and best cross validation giving hyperparameters are used as tuned param-
               eters. The performance of each of the classifiers is described in Section 4.5.





               4.6 RESULT AND ANALYSIS
               To evaluate the performance of the three classifiers along with the four feature extractors, 10-fold cross
               validation approach applied on the training set and then a test result was generated on the test set.




               4.6.1 10-FOLD CROSS VALIDATION RESULT
               The below Table 4.5 describes the 10-fold cross validation accuracy on the training set for the different
               combinations of feature extractor and classifiers along with different magnification factors of the
               images.




               4.6.2 MAGNIFICATION FACTOR WISE ANALYSIS ON VALIDATION ACCURACY
               4.6.2.1 Validation accuracy of 40×
               Interpretation: On the 40  data, almost all of the combinations of feature extractors and classifiers
               gave a validation accuracy above 90% and among them the ResNet-50 and LR classifier gave the best
               cross validation score of 94.17% (Fig. 4.7).
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