A Comprehensive Framework for Semantic Similarity Analysis of Human and AI-Generated Text Using Transformer Architectures and Ensemble Techniques
Lifu Gao, Ziwei Liu, Qi Zhang
TL;DR
The paper tackles AI-generated text detection by reframing the problem as semantic similarity analysis, arguing that semantic structure differentiates human and machine writing more than surface features. It introduces a multi-layer architecture built on DeBERTa-v3-large, enhanced with Bi-LSTM, linear attention pooling, and adversarial robustness tricks, plus sector-context augmentation and dynamic target shuffling to improve generalization. An extensive ensemble strategy, including Electra-based variants and wide-output configurations, combined with a Pearson-based loss and auxiliary MSE, yields state-of-the-art performance across Pearson correlation, MSE, F1, and AUC on diverse data. The work demonstrates strong practical potential for AI-generated text detection and related semantic-difference tasks, with future directions toward domain-specific pretraining and broader augmentation techniques for even better generalization.
Abstract
The rapid advancement of large language models (LLMs) has made detecting AI-generated text an increasingly critical challenge. Traditional methods often fail to capture the nuanced semantic differences between human and machine-generated content. We therefore propose a novel approach based on semantic similarity analysis, leveraging a multi-layered architecture that combines a pre-trained DeBERTa-v3-large model, Bi-directional LSTMs, and linear attention pooling to capture both local and global semantic patterns. To enhance performance, we employ advanced input and output augmentation techniques such as sector-level context integration and wide output configurations. These techniques enable the model to learn more discriminative features and generalize across diverse domains. Experimental results show that this approach works better than traditional methods, proving its usefulness for AI-generated text detection and other text comparison tasks.
