A General Theory of Classificatory Sorting Strategies: 1. Hierarchical Systems

It is shown that the computational behaviour of a hierarchical sorting-strategy depends on three properties, which are established for five conventional strategies and four measures. The conventional strategies are shown to be simple variants of a single linear system defined by four parameters. A new strategy is defined, enabling continuous variation of intensity of grouping by variation in a single parameter. An Appendix provides specifications of computer programs embodying the new principles.