When dynamically grouping a plurality of graphic objects, such as displayed on a graphic input display apparatus, a cluster tree is formed for the plurality of graphic objects. The cluster tree is based on a plurality of different types of distance measures. These include a time distance and a spatial distance. These distances are combined to form a distance metric indicting a distance between a pair of the graphic objects. Each level of the cluster tree defines a new cluster of the graphic objects. At least one of the graphic objects is selected. The different cluster levels of the cluster tree containing the selected graphic object are displayable. The displayed cluster of the graphic objects can be modified to increase or decrease the cluster level of the cluster containing the selected graphic object.