15. The text processing method according to claim 14 , wherein the (b) step comprises deriving, based on the result of the determination in the (a) step, an extent to which the content of the homogeneous segment is included in the second text corresponding to the other first text which includes the homogeneous segment, further deriving, based on the derived extent, a degree to which each segment constituting the first text which is set as the analysis target should be described in the second text corresponding to the first text which is set as the analysis target, and performing the determination using the degree.
15. The text processing method according to claim 14 , wherein the (b) step comprises deriving, based on the result of the determination in the (a) step, an extent to which the content of the homogeneous segment is included in the second text corresponding to the other first text which includes the homogeneous segment, further deriving, based on the derived extent, a degree to which each segment constituting the first text which is set as the analysis target should be described in the second text corresponding to the first text which is set as the analysis target, and performing the determination using the degree. 19. The text processing method according to claim 15 , wherein the (b) step comprises deriving, as the extent of inclusion in the second text, a frequency at which the content of the homogeneous segment is described in the second text corresponding to the other first text which includes the homogeneous segment, further deriving a degree to which each segment constituting the first text which is set as the analysis target should be described in the second text corresponding to the first text which is set as the analysis target, such that the degree increases the higher the frequency, and performing the determination using the derived degree.