2. The transliteration device according to claim 1 , further comprising: an initiator initializing weighting parameters for said K transliteration tables each indicating a ratio of the number of the original spelling strings originating from the implicit language corresponding to each of said K transliteration tables to the number of multiple original spelling strings included in said training set, wherein said updater calculates, for each of the multiple transliteration pairs included in said training set, an origin probability said original spelling string originates in the implicit language corresponding to the transliteration table based on the weighted average by said weighting parameters of the transliteration probabilities included in said K transliteration tables, so updates said K weighting parameters as to maximize said expected value of the likelihood function that is calculated further using the origin probability, and repeats said calculation of the origin probability and said update of the weighting parameters.
2. The transliteration device according to claim 1 , further comprising: an initiator initializing weighting parameters for said K transliteration tables each indicating a ratio of the number of the original spelling strings originating from the implicit language corresponding to each of said K transliteration tables to the number of multiple original spelling strings included in said training set, wherein said updater calculates, for each of the multiple transliteration pairs included in said training set, an origin probability said original spelling string originates in the implicit language corresponding to the transliteration table based on the weighted average by said weighting parameters of the transliteration probabilities included in said K transliteration tables, so updates said K weighting parameters as to maximize said expected value of the likelihood function that is calculated further using the origin probability, and repeats said calculation of the origin probability and said update of the weighting parameters. 4. The transliteration device according to claim 2 , wherein: said generator generates said K transliteration tables corresponding to K languages by generating one of said transliteration tables by an αβ method using one of said rewriting tables and altering the transliteration probability included in said one generated transliteration table; and said updater updates the transliteration probabilities included in said K transliteration tables, respectively, using an EM algorithm.