10. The method of claim 1 , wherein modifying further comprises: determining that a term of the second plurality of terms is not in the list of secondary terms; calculating the miss score for the term according to the frequency of the term in a corpus of documents; determining that the count of the term exceeds a threshold relative to the magnitude of the miss score of the term; and adding the term to the list of secondary terms, based on the determination that the count exceeds the threshold value.
1. A method for following a topic in an electronic textual conversation, the method comprising: selecting, by a computing device, one or more primary terms related to a topic; sending, by the computing device, to at least one communication service, a first query containing the at least one primary term; receiving, by the computing device, from the at least one communication service, at least one first set of messages responsive to the first query; for each first set, extracting, by the computing device, from the first set of messages, a first plurality of additional terms; for each term of the first plurality of additional terms, enumerating, by the computing device, the messages of the first set in which the term appears and adding the term to a list of secondary terms if the enumeration exceeds a threshold amount; sending, by the computing device, to the at least one communication service, at least one second query containing the at least one primary term and the set of secondary terms; receiving, by the computing device, from the at least one communication service, at least one second set of messages responsive to each second query; for each second set of messages: extracting, by the computing device, from the second set of messages, a second plurality of terms; determining, by the computing device, a corresponding set of previously received messages having a related set of secondary terms; for each term of each set of secondary terms relating to the corresponding set of messages and of the second plurality of terms, counting, by the computing device, the messages of the corresponding set and the second set in which the term and either (i) one of the at least one primary term or (ii) at least two of the secondary terms appears; and modifying, by the computing device, the list of secondary terms, based on the count for each term and a miss score calculated for each term.