Ensemble SFs computed from 200 mock light curves for the g (left), W1 (middle), and W2 (right) bands. Upward and downward triangles denote the ensemble SFs for the brightening and dimming phases, respectively, and the solid line denotes the ensemble SFs for all phases. Black triangles represent the ensemble SFs following a DRW model, while magenta and blue triangles represent those with global increasing and decreasing trends in brightness, respectively. The SF value was shifted arbitrarily to improve the clarity of the visualization.