Distinct suffix counts of 2 and above are stored by subtracting this proxy count and converting to the log quantisation scheme described above, i.e., In testing for a suffix count, we first query the item c(w 1 , ..., w n ) = 1 as a proxy for s(w 1 , ..., w n ) = 1 and, if found, query the filter for incrementally larger suffix counts, taking the reconstructed suffix count of an n-gram with a non-zero n-gram count to be the expected value, i.e., Having created a BF containing these events, the algorithm we use to compute the interpolated WB estimate makes use of the inequalities described above to reduce the a priori probability of querying for a negative.
we bound the count of each numerator in the maximum likelihood term by the count of the corresponding denominator and the count of distinct suffixes of an n-gram by its respective token frequency.