TABLE 7.

Feature groups and specific features for each group.

Feature group	Features
Pupil size	Pupil diameter
Fixation behaviors	Fixation count, fixation frequency, fixation duration total, fixation duration average
Fixation behaviors in AOIs	Fixation count, fixation time percentage in the QT, NO, NK, PO, PK, EO, and MO areas

AOIs, areas of interest; QT, the question text; NO, the extreme negative option; NK, the negative keyword; PO, the extreme positive keyword, PK, the positive keyword; EO, the extreme options; MO, the medium options.