Vasantharan K


2025

pdf bib
The_Deathly_Hallows@DravidianLangTech 2025: AI Content Detection in Dravidian Languages
Kogilavani Shanmugavadivel | Malliga Subramanian | Vasantharan K | Prethish G A | Vijayakumaran S
Proceedings of the Fifth Workshop on Speech, Vision, and Language Technologies for Dravidian Languages

The DravidianLangTech@NAACL 2025 shared task focused on Detecting AI-generated Product Reviews in Dravidian Languages, aiming to address the challenge of distinguishing AI-generated content from human-written reviews in Tamil and Malayalam. As AI generated text becomes more prevalent, ensuring the authenticity of online product reviews is crucial for maintaining consumer trust and preventing misinformation. In this study, we explore various feature extraction techniques, including TF-IDF, Count Vectorizer, and transformer-based embeddings such as BERT-Base-Multilingual-Cased and XLM-RoBERTa-Large, to build a robust classification model. Our approach achieved F1-scores of 0.9298 for Tamil and 0.8797 for Malayalam, ranking 8th in Tamil and 11th in Malayalam among all participants. The results highlight the effectiveness of transformer-based embeddings in differentiating AI-generated and human-written content. This research contributes to the growing body of work on AI-generated content detection, particularly in underrepresented Dravidian languages, and provides insights into the challenges unique to these languages.

pdf bib
The_Deathly_Hallows@DravidianLangTech 2025: Multimodal Hate Speech Detection in Dravidian Languages
Kogilavani Shanmugavadivel | Malliga Subramanian | Vasantharan K | Prethish G A | Santhosh S
Proceedings of the Fifth Workshop on Speech, Vision, and Language Technologies for Dravidian Languages

The DravidianLangTech@NAACL 2025 shared task focused on multimodal hate speech detection in Tamil, Telugu, and Malayalam using social media text and audio. Our approach integrated advanced preprocessing, feature extraction, and deep learning models. For text, preprocessing steps included normalization, tokenization, stopword removal, and data augmentation. Feature extraction was performed using TF-IDF, Count Vectorizer, BERT-base-multilingual-cased, XLM-Roberta-Base, and XLM-Roberta-Large, with the latter achieving the best performance. The models attained training accuracies of 83% (Tamil), 88% (Telugu), and 85% (Malayalam). For audio, Mel Frequency Cepstral Coefficients (MFCCs) were extracted and enhanced with augmentation techniques such as noise addition, time-stretching, and pitch-shifting. A CNN-based model achieved training accuracies of 88% (Tamil), 88% (Telugu), and 93% (Malayalam). Macro F1 scores ranked Tamil 3rd (0.6438), Telugu 15th (0.1559), and Malayalam 12th (0.3016). Our study highlights the effectiveness of text-audio fusion in hate speech detection and underscores the importance of preprocessing, multimodal techniques, and feature augmentation in addressing hate speech on social media.

2023

pdf bib
KEC_AI_NLP_DEP @ LT-EDI : Detecting Signs of Depression From Social Media Texts
Kogilavani Shanmugavadivel | Malliga Subramanian | Vasantharan K | Prethish Ga | Sankar S | Sabari S
Proceedings of the Third Workshop on Language Technology for Equality, Diversity and Inclusion

The goal of this study is to use machine learning approaches to detect depression indications in social media articles. Data gathering, pre-processing, feature extraction, model training, and performance evaluation are all aspects of the research. The collection consists of social media messages classified into three categories: not depressed, somewhat depressed, and severely depressed. The study contributes to the growing field of social media data-driven mental health analysis by stressing the use of feature extraction algorithms for obtaining relevant information from text data. The use of social media communications to detect depression has the potential to increase early intervention and help for people at risk. Several feature extraction approaches, such as TF-IDF, Count Vectorizer, and Hashing Vectorizer, are used to quantitatively represent textual data. These features are used to train and evaluate a wide range of machine learning models, including Logistic Regression, Random Forest, Decision Tree, Gaussian Naive Bayes, and Multinomial Naive Bayes. To assess the performance of the models, metrics such as accuracy, precision, recall, F1 score, and the confusion matrix are utilized. The Random Forest model with Count Vectorizer had the greatest accuracy on the development dataset, coming in at 92.99 percent. And with a macro F1-score of 0.362, we came in 19th position in the shared task. The findings show that machine learning is effective in detecting depression markers in social media articles.