22. The program according to claim 17 that causes the computer to correct the language model such that a priority of a word or word string that has appeared in the analyzed text data becomes higher in accordance to the different points between the analyzed text data and the virtual text data in the updating process.
22. The program according to claim 17 that causes the computer to correct the language model such that a priority of a word or word string that has appeared in the analyzed text data becomes higher in accordance to the different points between the analyzed text data and the virtual text data in the updating process. 23. The program according to claim 22 that causes the computer to control an amount of changing of the priority in accordance to a frequency of occurrence of the word or word string in the analyzed text data and the virtual text data in the updating process.