Text Analysis Learning Strategies

TEXT ANALYSIS LEARAING STrATEGiES Pierre PLANTE Universit@ du Qu@bec ~ Montr@al APLEC (l'APrenti-LECteur or Learning Reader) is an extension of the D@redec software, a programming system devoted to the content analysis and linguistic treatment of texts. APLEC will associate automatically to any text descriptive grammar (TDG Grammaire descriptive de texte) a question/answer module where the questions are asked in a given natural language by the user, and where the a~wers are tracked down in the textual corpus undergoing examination. The user's TDGs can inscribe themselves at various levels of analysis (morphological, syntactical, semantical, logical, ...), and it is a singular characteristic of the D@redec that it allows for a polyvalent treatment without interfaces, this being done with only one retentive structure for the information, and only one algorithmic structure for the description and for the retrieval. Once the user's TDG is applied on the question (it was at first applied on the whole of the text), some exploration models (provided by the user) activate the comparison of the question to the text in order to initiate the tracking down of the answer. If, due to weaknesses of the grammar, APLEC cannot bring to an end this work, it will track down relevant elements of the problem lifted up, communicate with the user, submit to him the results of its analysis, and wait for him to propose a solution to the problem. If there is such a solution, it will be further on 'learned' by APLEC, that is it will be generalized on the whole text in such a way as APLEC will no more intervene if similar problems arise again. Hence, the intelligence of the analysis grows gradually as the work of the interactions between the user and his text, via the automaton, goes on; and it shall construct itself by osmosis to the particular semantics of the text undergoing questioning. We do not pretend to supply an achieved theory of automatic learning, but rather try to supply different formal strategies functioning whatever the content of the D@redec grammars applied to a given text. I will first describe the general characteristics of the D@redec programming system, and afterwards will pass on to a few examples of utilization of the question module named APLEC. The D@redec offers to its users two large classes of functions: (i) functions said to be text descriptive, and (ii) text ex~lorative ~unctions. The first functions have the form of finished state automata. They are machines that scan the text sequence after sequence (e.g. sentences), and that build tree structures onto the elements of these sequences (e.g. words). The knots of the trees are labelled with descriptive categories, and are also, eventually, linked together by oriented relations. The leaves of the trees (the words of the sequences) can see themselves adjoined with complex semantic networks.