Performance and computational cost comparison on test sets (three-fold cross-validation). The plots display the average performance in terms of RMSE (left y-axis) and training time in minutes (right y-axis) for the Alcock (left) and ATLAS (right) datasets, varying the number of samples per class (SPC). Red bars (pretrained) represent the pretrained model evaluated directly on the test set without fine-tuning. Turquoise bars (finetuned) show performance after fine-tuning with the indicated amount of data. Hatched beige bars indicate the fine-tuning time required. Error bars denote the range (minimum and maximum values) observed across the three folds.