A New Two-Stage Approach to the Multiaspect Text Categorization

Multiaspect Text Categorization Problem Solving: A Nearest Neighbours Classifier Based Approaches and Beyond

“…In the MTC problem the situation is different and the order of the documents within a case may be assumed to convey some extra information which may be exploited for their proper classi ication. In [25] we have shown that the documents can be quite successfully classi ied to the cases by their comparison just to the last document of candidate cases. Thus, it seems to con irm that the similarity to the most recent documents in a case should in luence most the classi ication decision.…”

“…We consider the task of the system as of the decision support type, i.e., a human user should be assisted by the system in choosing a proper category c ∈ C and a proper a case σ ∈ Σ for the document d * but he or she is responsible for performing these actions. Several ways of assigning documents to categories/cases may be conceived; cf., e.g., [23,25]. We follow here the line of conduct presented in the latter paper, i.e., of a two stage assignment: irst to a category and then to a case.…”

“…In our previous work [25] on the solution of the MTC problem we already proposed to use the k-nn technique for the irst stage of the solution, i.e., deciding on the category to which the newly classi ied document d * belongs as well as to the second stage, i.e., assigning the document d * to a case. Here we study some extensions to the basic k-nn procedure and compare them experimentally with the approaches proposed by Yang et al [20] which are presented in section 3.1.…”

“…The index (10) introduced here is used to assign new document D * to a case in a straightforward way (we assume that before that d * is assigned to a category c using, e.g., the basic k-nn algorithm, as in our previous paper [25]): 1) the matching index m de ined by (10) is computed for all candidate (on-going) cases belonging to category c; the set of such cases is denoted as Σ c , 2) the document d * is assigned to the case σ * such that:…”

“…Our starting point is the concept of the multiaspect text categorization (MTC) which we introduced earlier in a series of papers [9,22,23,25]. The motivation is a real, practical problem of managing collections of documents for the purposes of an organization, notably a public institution which has to be carried out following formal regulations imposed by the state.…”