2. The language model score look-ahead value imparting device according to claim 1 , wherein the smoothing language model score look-ahead value calculation unit obtains the language model score look-ahead value at each phoneme in the word based on an appearance order of the phoneme in the word.
3. The language model score look-ahead value imparting device according to claim 2 , wherein the smoothing language model score look-ahead value calculation unit obtains the language model score look-ahead value at each phoneme in the word based on the number of phonemes from a word head to the phoneme.