An arithmetic processor including: a selection unit configured for a user to select a color that satisfies a predetermined condition with respect to a reference color formed on a medium that reflects light, out of a plurality of different colors displayed on a display apparatus a determination unit configured to determine colors to be displayed on the display apparatus next time, based on the color selected by the user and a calculation unit configured to calculate a visual characteristic of the user, based on results of repeating the determination of colors by the determination unit and the selection by the user for a plurality of times. In a case where the user repeatedly selects a color out of a combination of colors, the calculation unit calculates the visual characteristic of the user, based on the colors included in the combination.
