Algorithmic Selection of the Best Method for Compressing Map Data Strings The best of a dozen different methods for compressing map data is illustrated. The choices are generated by encoding data strings-sequence of like codes-by three methods and in four directions. Relationships are developed between compression alternatives to avoid comparing all of them. The technique has been used to compress data from forest resource maps, but is widely applicable to map and photographic data reduction. CACM December, 1971 Amidon, E. L. Akin, G. S. data compression, map storage, information retrieval, input/output, run coding, data reduction 3.71 3.74 CA711202 JB February 2, 1978 10:23 AM 2141 5 2141 2141 5 2141 2141 5 2141