z Conclusion Either of the predictive information quantity of the first word and the second word in the objective word sequence is larger than that of the headword of the parent node which has the largest predictive information quantity among all of the history feature type candidates.
according to the above idea, we build the information-theory-based feature type analysis model, which is composed of four concepts: predictive information quantity, predictive information gain, predictive information redundancy and predictive information summation.