13. A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed by a processor, cause the processor to perform a method comprising: acquiring a feature amount for respective tags, wherein each of the tags being assigned to character strings included in a shared markup text, at least one of the tags being different from other tags, and the acquiring of the feature amount changes a similarity according to an instruction signal; calculating, for respective character strings, a dispersion of feature amounts of the tags; detecting a first character string assigned with a first tag having the dispersion not less than a first threshold value as a first candidate including the first tag to be corrected; and outputting the first candidate.
13. A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed by a processor, cause the processor to perform a method comprising: acquiring a feature amount for respective tags, wherein each of the tags being assigned to character strings included in a shared markup text, at least one of the tags being different from other tags, and the acquiring of the feature amount changes a similarity according to an instruction signal; calculating, for respective character strings, a dispersion of feature amounts of the tags; detecting a first character string assigned with a first tag having the dispersion not less than a first threshold value as a first candidate including the first tag to be corrected; and outputting the first candidate. 17. The computer readable medium according to claim 13 , further comprising assigning the tags to the character strings based on markup text edited by at least one or more users.