An illustration of VISDA on sample clustering. (a) The five different projections obtained at the top level. Red circles are brain cancer; green triangles are colon cancer; blue squares are lung cancer; and brown diamonds are ovary cancer. (b) The user's initialization of cluster means (indicated by the numbers in the small circles) and the resulted clusters (indicated by the green dashed ellipses). The left, middle, and right figures are for the models of one cluster, two clusters, and three clusters, respectively. (c) The hierarchical data structure detected by VISDA. Sub-Cluster Number (CN) and corresponding Description Length (DL) are shown under the visualization.