To analyze a chronological accommodation process for viewing objects, viewer's VEP, eye movements and pupil oscillations were measured while six sizes of Landolt circle were presented for 1s, with reviews being asking and then not being asking for their responses right afterwards. The significant features of the metrics were extracted to illustrate the perception process and resulting sizes of visual stimuli. The stimulus sizes affect P1 and N1 delay times of VEP, mean of eye movement lengths and pupil diameters and oscillations during the second 500 {milliseconds}. The feasibility of prediction for stimulus sizes viewed is been confirmed using the indices and support vector machines. Also, both indices of eye movements and pupil oscillations are determined to be significant features for predictions. This result suggests that oculo-motor indices reflect the size of objects being viewed and can be an index of prediction for the viewing sizes.