• 1999
• Domain Map
• Exhibit map

Dr. Henry Small has pioneered mapping the structure of science based on scholarly publications, yet independent of existing disciplinary categories. The very first map of all of science is shown here. A combination of fractional citation counting and co-citation clustering via multidimensional scaling was used to extract four nested levels of clustering via single and complete linkage. Major disciplines of science emerge from a bottom-up aggregation of highly cited papers. They are displayed in two dimensions, using an order-dependent, geometric triangulation process that produces a unified hierarchical arrangement of documents. Each circle contains a map of similar construction at a lower level of aggregation. Circle size corresponds to the number of citations received by documents in each cluster. Links among circles represent aggregate document co-citations. The original set up facilitated the interactive exploration of the nested hierarchy of scientific disciplines.