Figure 3.

K-fold cross validation.*

*The datasets are divided into several, equally sized subsets. The model is trained on subsets (training sets). After the training process, the model is tested on the remaining subsets (test sets). According to the number of subsets partitioned, user tests k-fold cross-validation. In ten-fold cross-validation, for example, one may use 10 results of 10-fold cross-validation.