Core Viewpoint - The article introduces the LensLLM framework developed by Virginia Tech, which significantly enhances the efficiency of selecting large language models (LLMs) while reducing computational costs, thus addressing the challenges faced by researchers and developers in model selection [2][3][4]. Group 1: Introduction - The rapid advancement of LLMs has created a challenge in model selection, as traditional methods are resource-intensive and yield limited results [4]. Group 2: Theoretical Breakthrough of LensLLM - LensLLM is based on a novel PAC-Bayesian Generalization Bound, revealing unique dynamics in the relationship between test loss and training data size during LLM fine-tuning [6][10]. - The framework provides a first-principles explanation of the "phase transition" in LLM fine-tuning performance, indicating when data investment leads to significant performance improvements [12][16]. Group 3: LensLLM Framework - LensLLM incorporates Neural Tangent Kernel (NTK) to accurately capture the complex dynamics of transformer architectures during fine-tuning, establishing a precise relationship between model performance and data volume [15][16]. - The framework demonstrates impressive accuracy in curve fitting and test loss prediction across various benchmark datasets, outperforming traditional models [17][18]. Group 4: Performance and Cost Efficiency - LensLLM achieved a Pearson correlation coefficient of 85.8% and a relative accuracy of 91.1% on the Gigaword dataset, indicating its effectiveness in ranking models [21]. - The framework reduces computational costs by up to 88.5% compared to FullTuning, achieving superior performance with significantly lower FLOPs [23][25]. Group 5: Future Prospects - The research opens new avenues for LLM development and application, with potential expansions into multi-task scenarios and emerging model architectures like Mixture of Experts (MoE) [27][30]. - LensLLM is particularly suited for resource-constrained environments, accelerating model testing and deployment cycles while maximizing performance [31].