This measure originates in work on lexical priming (Church, 2000), and quantifies the probability of a target word or construction w appearing in a "primed" context.
four frequencies are calculated, based on whether the target construction appears in the previous context (the prime set), and whether the construction appears after this context (the target set): f p,¬t (w) = # of times w in prime set only f ¬p,t (w) = # of times w in target set only f ¬p,¬t (w) = # of times w in neither set f p,t (w) = # of times w in both sets We also define N to be the sum of the four fre-LHS prior pos adapt ratio + > prior sig.