EXPRESSION EXTRACTION DEVICE, EXPRESSION EXTRACTION METHOD, AND RECORDING MEDIUM

Provided is an expression extraction device for extracting evaluation expressions from text having descriptions on evaluations of a specific evaluation target, which includes a registered expression storage unit for registering an evaluation expression including a predetermined polarity as a registered expression, an expression extraction unit for extracting multiple evaluation expressions and a conjunction expression from the text, a registered expression detection unit for detecting the evaluation expression including the registered expression registered with the registered expression storage unit out of the multiple evaluation expressions, and a polarity judgment unit for judging that the evaluation expression, which is in conjunction with the evaluation expression including the registered expression by means of the conjunction expression in a form of ordinary conjunction, and the series of evaluation expressions, which are not in conjunction with the evaluation expression by means of the conjunction expression in any form of the ordinary conjunction and adversative/concessive conjunction and are not in conjunction with each other by means of the conjunction expression in any form of the ordinary conjunction and the adversative/concessive conjunction, are of the same polarity as the registered expression.