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Figure 3: The architecture of the VGG16 convolutional neural network.

5. RESULTS Metrics Baseline GWOTLT

The obtained performance results from the conducted ex- Time [s] 49.10 ± 1.85 759.10 ± 59.67
periments are summarized in Table 3. Focusing on the time AUC [%] 87.00 ± 9.19 91.00 ± 7.75
metrics, the reported results are expected, with the lowest F − 1 [%] 86.27 ± 11.03 91.45 ± 6.81
time complexity being achieved by the Baseline method. On Precision [%] 88.62 ± 10.37 90.89 ± 11.36
the other side, the proposed GWOTLT method is expected Recall [%] 86.00 ± 17.13 93.00 ± 6.75
to have a higher time complexity in general due to the it-
erative nature of the proposed method. In our case, the Kappa 0.74 ± 0.18 0.82 ± 0.15
GWOTLT method performed worse in the aspect of time
complexity, roughly by a factor 15. Table 3: Comparison of average times, accuracies,
AUCs, F − 1 scores, precisions, recalls and kappa
Analyzing presented classification performance metrics, the coefficients with standard deviations over 10-fold
GWOTLT method is standing out with achieved best results cross-validation.
on all of the reported performance metrics. The AUC, F −1,
precision and recall metrics are higher by a margin of 4%, In the future, we would like to expand our work to include
5.18%, 2.27%, 7% respectively in comparison to the baseline various CNN architectures as a convolutional base for our
method. Focusing on the kappa coefficient values, we can ob- GWOTLT method and also evaluate the performance of the
serve that the GWOTLT achieved a near-perfect agreement proposed method against various medical imaging datasets.
with kappa coefficient at 0.82 and outperformed the base-
line method by a margin of 0.08. Looking at the standard Acknowledgments
deviations of the reported classification average metric val-
ues, we can observe that for all classification metrics, except The authors acknowledge the financial support from the
for the precision, the best performing GWOTLT method is Slovenian Research Agency (Research Core Funding No. P2-
showing the smallest standard deviation. The greatest im- 0057).
provement of lowering the standard deviation the GWOTLT
achieved for the recall metric by a margin of 10.38%, while 7. REFERENCES
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