 In one form, the latent class model is written as
where formula_2 is the number of latent classes and formula_3 are the so-called recruitment
or unconditional probabilities that should sum to one.formula_4 are the
marginal or conditional probabilities.For a two-way latent class model, the form is
This two-way model is related to probabilistic latent semantic analysis and non-negative matrix factorization.