Multifractal discrimination model (MDM) of high-frequency pupil diameter measurements for human-computer interaction

Multifractality present in High-Frequency pupil diameter measurements, usually connected with the irregular scaling behavior and Self-Similarity, is modeled with statistical accuracy and discriminatory power. The Mul-tifractal Discrimination Model (MDM) is proposed to determine ocular pathology based on the pupillary response behavior (PRB) exhibited by older adults with and without ocular disease during the performance of a Computer-Based task. The MDM consists of two parts: (1) a dis-criminatory summary of the multifractal spectrum and (2) a combined K-Nearest-Neighbor classifier. The multifractal spectrum is used to Dis-Criminate the PRB from four groups of older adult users, differing in oc-ular pathology. Spectral Mode, Broadness, and left Slope (the M.B.S. summary), three measures characterizing the multifractal spectrum of observations, are proposed as distinguishing features of PRB across the groups. The combined K-Nearest neighbor classifier is shown to be a valid classifier for the accurate prediction of ocular pathology from the PRB measurements.