BERT Fine-Tuning for Software Requirements Classification: Impact of Model Components and Dataset Size

Recent advances in natural language processing (NLP) have enabled the automation of Software Requirements Classification (SRC), particularly through fine-tuning models such as Bidirectional Encoder Representations from Transformers (BERT). While BERT-based models have shown promising results, the impact of hyperparameter sensitivity and dataset size on SRC performance remains underexplored. To address this gap, we present three main contributions: (1) the development and evaluation of BERT fine-tuning for SRC, with emphasis on the effects of key hyperparameters and dataset size; (2) comprehensive experiments to analyze the influence of individual hyperparameters to identify optimal configurations for robust and efficient performance; and (3) controlled experiments highlighting the critical factors that affect the fine-tuning outcomes in SRC, particularly dataset size and hyperparameter sensitivity. Our approach was assessed on two datasets: the PROMISE NFR dataset and FR_NFR, a tailored dataset for the SRC task. The proposed method outperformed baseline models, achieving an average F1-score of 0.99 on PROMISE and 0.97 on FR_NFR. These findings provide empirical evidence on optimization strategies for BERT-based requirements classification and offer practical guidance to software engineering practitioners.