Praboda Rajapaksha
Author directory2026
Disentangling Topology and Diversity in Multi-Agent LLMs for Multilingual Low-Resource Emotion Detection
Ulugbek Shernazarov | Charitha Ruwansiri Weerakon Basnayake | Abdelkhaleq El Jarjini | Noel Crespi | Praboda Rajapaksha
Proceedings of the Second Workshop for REsearch on Agent Language Models (REALM 2026)
Ulugbek Shernazarov | Charitha Ruwansiri Weerakon Basnayake | Abdelkhaleq El Jarjini | Noel Crespi | Praboda Rajapaksha
Proceedings of the Second Workshop for REsearch on Agent Language Models (REALM 2026)
Multi-agent LLM systems combine multiple inference calls, but prior work often confounds how calls are connected with how they are diversified. We study these factors independently: inference topology and source of inter-agent diversity. In a controlled 2 x 3 matrix, we cross parallel aggregation and sequential refinement with stochastic sampling, role prompting, and learned QLoRA specialization, under a fixed three-call budget and output protocol within each backbone. Using Qwen2.5-14B-Instruct and Llama-3.1-8B-Instruct, we evaluate all six configurations on multilingual low-resource emotion detection across nine languages. Parallel learned specialization is strongest on Qwen at 52.83 Macro-F1 and reaches 52.94 on Llama. On Qwen it also exceeds same-backbone zero-shot, few-shot, CoT, and seven-call self-consistency baselines. The preferred topology depends on diversity source: sequential refinement helps stochastic and prompted settings, while the learned Width advantage shrinks from 2.83 points on Qwen to 0.17 on Llama. Depth-wise analysis suggests that later learned specialists can overwrite correct early predictions, although the aggregate effect is backbone-dependent. Overall, how agents are differentiated produces larger performance shifts than topology, which should be evaluated jointly with specialization.
2025
SA-CLIP: Language Guided Image Spatial and Action Feature Learning
Guanlin Li | Wenhao Shao | Praboda Rajapaksha | Noel Crespi
Findings of the Association for Computational Linguistics: EMNLP 2025
Guanlin Li | Wenhao Shao | Praboda Rajapaksha | Noel Crespi
Findings of the Association for Computational Linguistics: EMNLP 2025
We observed that Contrastive Language-Image Pretraining (CLIP) models struggle with real-world downstream tasks such as road traffic anomaly detection, due to their inability to effectively capture spatial and action relationships between objects within images. To address this, we compile and curate a dataset with 1M samples of images using language supervision provided by the common image caption dataset, in which each image is paired with subject-relationship-object descriptions emphasizing spatial and action interactions, and train a Spatial and Action relationship aware CLIP (SA-CLIP) model. We evaluated the proposed model on the Visual Spatial Reasoning (VSR) dataset and further verified its effectiveness on the Detection-of-Traffic-Anomaly (DoTA) dataset. Experiment results show that the proposed SA-CLIP demonstrates strong abilities in understanding spatial relationships while achieving good zero-shot performance on the traffic anomaly detection task.