Sequence conversion apparatus, machine learning apparatus, sequence conversion method, machine learning method, and program

Abstract

A device, to perform highly accurate sequence conversion consistent with the context, uses a t-th word string Xof the first text and a sequence Y{circumflex over ( )}, . . . , Y{circumflex over ( )}of first to (t−1)-th word strings of the second text, which is a conversion result of a sequence X, . . . Xof first to (t−1)-th word strings of the first text to obtain a probability of copying a word from the t-th word string Xor the sequence Y{circumflex over ( )}, . . . , Y{circumflex over ( )}, on the basis of the model parameters θ, and estimates information corresponding to a t-th word string Yof the second text by copying a word from the t-th word string Xor the sequence Y{circumflex over ( )}, . . . , Y{circumflex over ( )}based on the probability of copying.