Lilia Simeonova


2019

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A Morpho-Syntactically Informed LSTM-CRF Model for Named Entity Recognition
Lilia Simeonova | Kiril Simov | Petya Osenova | Preslav Nakov
Proceedings of the International Conference on Recent Advances in Natural Language Processing (RANLP 2019)

We propose a morphologically informed model for named entity recognition, which is based on LSTM-CRF architecture and combines word embeddings, Bi-LSTM character embeddings, part-of-speech (POS) tags, and morphological information. While previous work has focused on learning from raw word input, using word and character embeddings only, we show that for morphologically rich languages, such as Bulgarian, access to POS information contributes more to the performance gains than the detailed morphological information. Thus, we show that named entity recognition needs only coarse-grained POS tags, but at the same time it can benefit from simultaneously using some POS information of different granularity. Our evaluation results over a standard dataset show sizeable improvements over the state-of-the-art for Bulgarian NER.

2017

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Gradient Emotional Analysis
Lilia Simeonova
Proceedings of the Student Research Workshop Associated with RANLP 2017

Over the past few years a lot of research has been done on sentiment analysis, however, the emotional analysis, being so subjective, is not a well examined dis-cipline. The main focus of this proposal is to categorize a given sentence in two dimensions - sentiment and arousal. For this purpose two techniques will be com-bined – Machine Learning approach and Lexicon-based approach. The first di-mension will give the sentiment value – positive versus negative. This will be re-solved by using Naïve Bayes Classifier. The second and more interesting dimen-sion will determine the level of arousal. This will be achieved by evaluation of given a phrase or sentence based on lexi-con with affective ratings for 14 thousand English words.