1. A method for classifying a plurality of objects displayed on a display device and displaying the classified plurality of objects, the method comprising: selecting, by one or more processors, one object from a plurality of objects as a selected object, wherein said selecting is performed in response to a user performing an object selection operation; and classifying, by one or more processors, the plurality of objects, wherein classification of each of the plurality of objects is based on a degree of association with the selected object, and wherein said classifying the plurality of objects comprises: reading, by one or more processors, a feature setting for computation of the degree of association; specifying, by one or more processors, a plurality of features that are subject to the computation of the degree of association; computing, by one or more processors and for each of the plurality of objects, the degree of association based on a difference in feature value from the selected object with regard to the plurality of features; and dividing, by one or more processors, the plurality of objects into a plurality of groups, wherein each group from the plurality of groups is based on the degree of association.