1. A language model creation device that creates a new language model using a standard language model created from standard language text, comprising: a transformation rule storage section that stores transformation rules used for transforming dialect-containing word strings into standard language word strings, and a dialect language model creation section that creates dialect-containing n-grams by applying the transformation rules to word n-grams in the standard language model and, furthermore, creates the new language model by adding the created dialect-containing n-grams to the word n-grams.