where <math>f_{XY}</math> is the number of times the bigram xy appears in the corpus, <math>f_{X}</math> is the number of times the unigram x appears in the corpus, B is the total number of bigrams, and U is the total number of unigrams. | where <math>f_{XY}</math> is the number of times the bigram xy appears in the corpus, <math>f_{X}</math> is the number of times the unigram x appears in the corpus, B is the total number of bigrams, and U is the total number of unigrams. |