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Introduced by Ralph Hartley in 1928.
Etymology from Wiktionary, CC BY-SA 4.0.
Hartley function
Today it means: A measure of uncertainty. If a sample from a finite set A uniformly at random is picked, the information revealed after the outcome is known is given by the Hartley function H_0(A):=log_b|A|, where |A| denotes the cardinality of A. Full definition →