11. An information extracting method comprising: collecting a text in which a keyword of interest indicating information of interest that a user is interested in, the keyword of interest, and a time of creation of the text; extracting a keyword included in the text except for the keyword of interest and configured to extract the time of creation; extracting the keyword having a time score obtained on the basis of an appearance frequency of the keyword in a time interval, which is a period T1 backward from the time of creation, exceeding a first threshold value and a local score on the basis of the appearance frequency of the keyword in a local area indicating a range of a specific topic exceeding a second threshold value as a local hot word, and also extract the extracted time interval of the keyword and the keyword of interest corresponding to the keyword; and storing the extracted local hot word, the time interval, and the keyword of interest.
12. The information extracting method according to claim 11 , further comprising: accepting a user text created by the user; extracting a user keyword included in the user text and a time of creation by the user of the user text; specifying the information of interest corresponding to the local hot word as the information of interest corresponding to the user text when the user keyword and the local hot word stored and the time of creation by the user is included in the time interval of the local hot word; and annotating the user text with the information of interest.