In these examples, the taxonomy 1800A includes category node 1801A through 1810A related to each other using relation types A, B and C. Taxonomy 1800B includes categories 1801B through 1808B related to each other using relation types B, C and D. Taxonomy 1800C includes categories 1801C through 1812C related to each other using relation types C, D and E. In this example, taxonomies 1800A and 1800B