Using of n-grams from morphological tags for fake news classification

PeerJ Comput Sci. 2021 Jul 19;7:e624. doi: 10.7717/peerj-cs.624. eCollection 2021.


Research of the techniques for effective fake news detection has become very needed and attractive. These techniques have a background in many research disciplines, including morphological analysis. Several researchers stated that simple content-related n-grams and POS tagging had been proven insufficient for fake news classification. However, they did not realise any empirical research results, which could confirm these statements experimentally in the last decade. Considering this contradiction, the main aim of the paper is to experimentally evaluate the potential of the common use of n-grams and POS tags for the correct classification of fake and true news. The dataset of published fake or real news about the current Covid-19 pandemic was pre-processed using morphological analysis. As a result, n-grams of POS tags were prepared and further analysed. Three techniques based on POS tags were proposed and applied to different groups of n-grams in the pre-processing phase of fake news detection. The n-gram size was examined as the first. Subsequently, the most suitable depth of the decision trees for sufficient generalization was scoped. Finally, the performance measures of models based on the proposed techniques were compared with the standardised reference TF-IDF technique. The performance measures of the model like accuracy, precision, recall and f1-score are considered, together with the 10-fold cross-validation technique. Simultaneously, the question, whether the TF-IDF technique can be improved using POS tags was researched in detail. The results showed that the newly proposed techniques are comparable with the traditional TF-IDF technique. At the same time, it can be stated that the morphological analysis can improve the baseline TF-IDF technique. As a result, the performance measures of the model, precision for fake news and recall for real news, were statistically significantly improved.

Keywords: Fake news identification; Morphological analysis; Natural language processing; POS tagging; Text mining.

Publication types

  • News

Grant support

This work was supported by the Scientific Grant Agency of the Ministry of Education of the Slovak Republic (ME SR) and Slovak Academy of Sciences (SAS) under the contract No. VEGA-1/0792/21, also by the scientific research project of the Czech Sciences Foundation Grant No:19-15498S and by the Slovak Research and Development Agency under the contract no. APVV-18-0473. There was no additional external funding received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.