Table 4.

Different strategies (BEST, CROSS, RANDOM, and ADAPT) to choose the model to predict test cases

Strategies	Details
BEST
E2E	Trained on Edinburgh data (80%), evaluated on Edinburgh data (20%).
S2S	Trained on Sheffield data (80%), evaluated on Sheffield data (20%).
CROSS
E2S	Trained on Edinburgh data (80%), evaluated on Sheffield data (20%).
S2E	Trained on Sheffield data (80%), evaluated on Edinburgh data (20%).
RANDOM	Pick a random model learned from either training set to evaluate a given test set.
ADAPT	Use our proposed method to choose model.