Explainable Detection of Depression Status Shifts from User Digital Traces

Every day, users generate digital traces (e.g., social media posts, chats, and online interactions) that are inherently timestamped and may reflect aspects of their mental state. These traces can be organized into temporal trajectories that capture how a user's mental health signals evolve, including phases of improvement, deterioration, or stability. In this work, we propose an explainable framework for detecting and analyzing depression-related status shifts in user digital traces. The approach combines multiple BERT-based models to extract complementary signals across different dimensions (e.g., sentiment, emotion, and depression severity). Such signals are then aggregated over time to construct user-level trajectories that are analyzed to identify meaningful change points. To enhance interpretability, the framework integrates a large language model to generate concise and human-readable reports that describe the evolution of mental-health signals and highlight key transitions. We evaluate the framework on two social media datasets. Results show that the approach produces more coherent and informative summaries than direct LLM-based reporting, achieving higher coverage of user history, stronger temporal coherence, and improved sensitivity to change points. An ablation study confirms the contribution of each component, particularly temporal modeling and segmentation. Overall, the method provides an interpretable view of mental health signals over time, supporting research and decision making without aiming at clinical diagnosis.

Dynamic hashtag recommendation in social media with trend shift detection and adaptation

The widespread use of social media platforms results in the generation of vast amounts of user-generated content, which requires efficient methods for categorization and search. Hashtag recommendation systems have emerged as a crucial tool for automatically suggesting relevant hashtags and improving content discoverability. However, existing static models struggle to adapt to the highly dynamic and real-time nature of social media conversations, where new hashtags emerge and existing ones undergo semantic shifts. To address these challenges, this paper presents H-ADAPTS (Hashtag recommendAtion by Detecting and adAPting to Trend Shifts), a BERT-based hashtag recommendation methodology that can detect and adapt to shifts in the main trends and topics underlying social media conversation. Our approach introduces a trend-aware detection mechanism to identify changes in hashtag usage, triggering efficient model adaptation on a (small) set of recent posts. The framework leverages Apache Storm for real-time stream processing, enabling scalable and fault-tolerant analysis of high-velocity social data. Experimental results on two real-world case studies, including the COVID-19 pandemic and the 2020 US presidential election, demonstrate the ability to maintain high recommendation accuracy by adapting to emerging trends. Our methodology significantly outperforms existing solutions, ensuring timely and relevant hashtag recommendations in dynamic environments.

Detecting mental disorder on social media: a ChatGPT-augmented explainable approach

In the digital era, the prevalence of depressive symptoms expressed on social media has raised serious concerns, necessitating advanced methodologies for timely detection. This paper addresses the challenge of interpretable depression detection by proposing a novel methodology that effectively combines Large Language Models (LLMs) with eXplainable Artificial Intelligence (XAI) and conversational agents like ChatGPT. In our methodology, explanations are achieved by integrating BERTweet, a Twitter-specific variant of BERT, into a novel self-explanatory model, namely BERT-XDD, capable of providing both classification and explanations via masked attention. The interpretability is further enhanced using ChatGPT to transform technical explanations into human-readable commentaries. By introducing an effective and modular approach for interpretable depression detection, our methodology can contribute to the development of socially responsible digital platforms, fostering early intervention and support for mental health challenges under the guidance of qualified healthcare professionals.

Block size estimation for data partitioning in HPC applications using machine learning techniques

The extensive use of HPC infrastructures and frameworks for running data-intensive applications has led to a growing interest in data partitioning techniques and strategies. In fact, finding an effective partitioning, i.e. a suitable size for data blocks, is a key strategy to speed-up parallel data-intensive applications and increase scalability. This paper describes a methodology for data block size estimation in HPC applications, which relies on supervised machine learning techniques. The implementation of the proposed methodology was evaluated using as a testbed dislib, a distributed computing library highly focused on machine learning algorithms built on top of the PyCOMPSs framework. We assessed the effectiveness of our solution through an extensive experimental evaluation considering different algorithms, datasets, and infrastructures, including the MareNostrum 4 supercomputer. The results we obtained show that the methodology is able to efficiently determine a suitable way to split a given dataset, thus enabling the efficient execution of data-parallel applications in high performance environments.