Generation of fixed‐length search codes from INSPEC words using techniques based on variety generation and on division‐hashing

The use of variety generation techniques in the production of fixed‐length degenerate representations for search terms is compared with methods based on division‐hashing. For files of words taken from INSPEC data, the latter perform better, almost certainly because of dependence between assignments of symbol sets. Attempts to overcome the problem produced no real improvement, possibly because the decrease in dependence was accompanied by an increased skewness in the distribution of symbols.