1. A colorimetric-data correcting method comprising: printing color patches in colors each corresponding to one of a plurality of coordinate points in an output color space defined for a printing device; measuring each color patch with a calorimeter to obtain calorimetric data for each color patch, the calorimetric data being represented by coordinate data in a device-independent standard color space; and correcting the calorimetric data for each of at least one color patch based on at least three (3) calorimetric data including the calorimetric data to be corrected.