... eration (Smadja and McKeown, 1990), lexicogra- phy (Church and Hanks, 1990), machine transla- tion (Brown et al., ; Sadler, 1989), information retrieval (Maarek and Smadja, 1989) and various disambiguation ... using frequency information (Good, 1953; Katz, 1987; Jelinek and Mercer, 1985; Church and Gale, 1991). Church and Gale (Church and Gale, 1991) show, that for unobserved bigrams, the estimates ... an eyent and N is the length of the corpus. While better es- timates for small probabilities are available (Good, 1953; Church and Gale, 1991), MLE is the simplest to implement and was adequate...