| Resumen |
The article presents the experiments carried out as part of the participation in the pilot task (Modality
and Negation)1 of QA4MRE@CLEF 2012. Modality and Negation are two main grammatical devices that allow
to express extra-propositional aspects of meaning. Modality is a grammatical category that allows to express
aspects related to the attitude of the speaker towards statements. Negation is a grammatical category that allows
to change the truth value of a proposition. The input for the systems is a text where all events expressed by verbs
are identified and numbered the output should be a label per event. The possible values are: mod, neg, neg-mod,
none. In the developed system, we first build a database for modal verbs of two categories: epistemic and deontic.
Also, we used a negative verb list of 1877 verbs. This negative verb list has been used to identify negative
modality. We extract the each tagged events from each sentences. Then our system check modal verbs by that
database from each sentences. If any modal verbs is found before that an event then that event should be modal
verb and tagged as mod. If modal verb is there and also negeted words is found before that evet then that event
should negeted mod and tagged as neg-mod. If no modal verb is found before that an event but negeted word are
found before that event then that event should be negeted and tagged as neg. Otherwise the event should tagged
as none. We trained our system by traing data (sample |
