A Weighted Maximum Entropy Language Model for Text Classification

Kostas Fragos, Yannis Maistros, Christos Skourlas



The Maximum entropy (ME) approach has been extensively used in various Natural Language Processing tasks, such as language modeling, part-of-speech tagging, text classification and text segmentation. Previous work in text classification was conducted using maximum entropy modeling with binary-valued features or counts of feature words. In this work, we present a method for applying Maximum Entropy modeling for text classification in a different way. Weights are used to select the features of the model and estimate the contribution of each extracted feature in the classification task. Using the X square test to assess the importance of each candidate feature we rank them and the most prevalent features, the most highly ranked, are used as the features of the model. Hence, instead of applying Maximum Entropy modeling in the classical way, we use the X square values to assign weights to the features of the model. Our method was evaluated on Reuters-21578 dataset for test classification tasks, giving promising results and comparably performing with some of the “state of the art” classification schemes.


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Paper Citation

in Harvard Style

Fragos K., Maistros Y. and Skourlas C. (2005). A Weighted Maximum Entropy Language Model for Text Classification . In Proceedings of the 2nd International Workshop on Natural Language Understanding and Cognitive Science - Volume 1: NLUCS, (ICEIS 2005) ISBN 972-8865-23-6X, pages 55-67. DOI: 10.5220/0002571800550067

in Bibtex Style

author={Kostas Fragos and Yannis Maistros and Christos Skourlas},
title={A Weighted Maximum Entropy Language Model for Text Classification},
booktitle={Proceedings of the 2nd International Workshop on Natural Language Understanding and Cognitive Science - Volume 1: NLUCS, (ICEIS 2005)},

in EndNote Style

JO - Proceedings of the 2nd International Workshop on Natural Language Understanding and Cognitive Science - Volume 1: NLUCS, (ICEIS 2005)
TI - A Weighted Maximum Entropy Language Model for Text Classification
SN - 972-8865-23-6X
AU - Fragos K.
AU - Maistros Y.
AU - Skourlas C.
PY - 2005
SP - 55
EP - 67
DO - 10.5220/0002571800550067