To get the DRS simplification model, we combine the probability of splitting with the probability of deletion: where θ is a sequence of simplification operations and str(θ(D c )) is the sequence of words associated with a DRS resulting from simplifying D c using θ.
the probability of a splitting operation for a given DRS D c is:  if the DRS is split on the splitting candidate sp cand , the probability of the split is then given by the SPLIt table (table 1) for the isSplit value "true" and the split candidate sp cand ; else it is the product of the probability given by the SPLIt table for the isSplit value "false" for all split candidate considered for D c .