conditional probability the probability of an observation when it depends on the outcome of some other observation, cf. Carol Ash (1993), pp. 37-45; e.g., the field values being in agreement is conditioned by there being two data values present in the field being compared, cf. Ch. 2, §2, ¶3 & RLG Chapter 5, §3, ¶2; the calculation of c. p. follows the principle of c. p., cf. Ch. 2, §2, ¶4