AI-Powered Natural Language Processing Framework for Reverse-Engineering Examination Questions from Marking Schemes

Abstract

The generation of examination questions from examiner-provided marking schemes remains a critical yet underexplored challenge in automated assessment. This study proposes an AI-powered natural language processing (NLP) framework that reverse-engineers exam questions using transformer-based generative modeling, semantic reconstruction, and pedagogical constraints. Marking schemes are encoded with MPNet embeddings and decoded into candidate questions by a T5-small model, with a reconstruction module ensuring semantic fidelity and Bloom-level embeddings enforcing cognitive alignment. Evaluation on a dataset of 7021 marking schemes from Sol Plaatje University demonstrated strong performance, with BLEU = 0.71, ROUGE-L = 0.68, METEOR = 0.65, reconstruction fidelity = 0.84, and Bloom-level accuracy = 0.79. Comparative baselines, including an unconstrained T5 (BLEU = 0.62, RF = 0.68, Bloom = 0.56) and rule-based methods (BLEU = 0.48, RF = 0.51, Bloom = 0.43), confirmed the effectiveness of the proposed approach. The results indicate that the framework generates questions that are semantically accurate, structurally coherent, and pedagogically valid, offering a scalable solution for adaptive assessment, digital archiving, and automated exam construction.