Catalogue of Artificial Intelligence Techniques
Keywords: SHRDLU, heterarchical system, hierarchical process organisation
Categories: Natural Language , Vision
Author(s): Aaron Sloman
In a hierarchical process organisation, data passes through a sequence of analytical or interpretive modules each of which acts independently of the rest. In a heterarchical system, modules may invoke other modules in the series to help with, for example, disambiguation of data. Winograd's program SHRDLU, in which syntactic analysis could make use of semantic modules on knowledge about the world was the most famous example. Shirai and others designed heterarchic image understanding programs. Heterarchy fell into disrepute when the work of Horn, Barrow and Tenenbaum suggested that far more disambiguation can be done autonomously by low levels than was previously thought. The fashion will change again when it is realised that in poor viewing conditions more sophisticated process organisation is required.
- Clowes, M.B., Man the creative machine, The limits of human nature (Benthall, J.
, ed.), Allen Lane, London, 1973.