coincidence 1) the probability that a specific value in two fields will agree in non-matched comparisons, i.e., by chance; 2) in practice the field’s non-specific c. is measured as the sum of the squares of the B-value of each possible field value, cf. general frequency, B-squared value, Ch. 2, §2, ¶7, RLG Chapter 3, §3, ¶6; in the latter case we distinguish two kinds of c.: general and entity, cf. RLG Chapter 4, §1