Stefano Bannò is a Research Associate at Cambridge University’s Institute for Automated Language Teaching and Assessment (ALTA) and the Machine Intelligence Lab (Department of Engineering), where he works on the intersection of AI, speech, and natural language processing for education. He completed his PhD in Cognitive Science at the University of Trento and Fondazione Bruno Kessler, focusing on the automatic assessment of L2 spoken English. His current research mostly focuses on learner-oriented feedback, fine-grained assessment of language proficiency, and spoken grammatical error correction. He has presented his work at leading international conferences, including Interspeech, ICASSP, SLT, SLaTE, BEA, COLING, and LREC. In 2023, he and his co-authors received the SLaTE Best Paper Award, and in 2024 his PhD thesis was a finalist for the Jacqueline Ross TOEFL Dissertation Award. Alongside his research, he currently serves as President of the College Research Associates at Emmanuel College. Outside academia, he has worked as a musician as well as a secondary school teacher.
Email: sb2549@cam.ac.uk
Title: "Towards Self-Referential Analytic Assessment: A Profile-Based Approach to L2 Writing Evaluation with LLMs"
Authors: Stefano Bannò, Kate Knill, Mark Gales
Paper link: https://arxiv.org/abs/2605.04298
Abstract: Automated essay scoring (AES) research often relies on rank-based correlation metrics to validate analytic assessment. However, such metrics obscure both intrinsic intercorrelations among analytic dimensions that arise from the structure of writing proficiency itself and halo effects, whereby holistic impressions bleed into fine-grained component scores. As a result, high correlations may mask a system’s true diagnostic behaviour. In this study, we propose a novel self-referential assessment evaluation framework that focuses on identifying intra-learner strengths and weaknesses rather than assessing inter-learner rankings. We conduct experiments on the publicly available ICNALE GRA, a uniquely dense second-language writing dataset annotated holistically and analytically by up to 80 trained raters. To obtain reliable reference scores, we apply two-facet Rasch modelling to calibrate rater severity and derive fair average scores across ten analytic aspects and holistic proficiency. We compare the analytic scoring performance of human operational raters and three large language models (LLMs) in a zero-shot setting. Our results show that LLMs tend to outperform single human raters in identifying relative weaknesses (negative feedback) across several proficiency aspects, while human raters remain stronger at identifying relative strengths (positive feedback). Overall, our findings highlight the limitations of rank-based evaluation for analytic assessment and demonstrate the value of intra-learner, profile-based methods for assessing and deploying LLMs in AES.