LoftQ: LoRA-Fine-Tuning-Aware Quantization for Large Language Models

Method

对QLoRA方法的改进,QLoRA在初始化时,

Q = Quantize(W)

A = 正态分布, B = 0

这种初始化方法非常差,导致模型在一开始就偏离最优解太多,最终导致训练变差,论文中使用LoftQ算法对Q, A, B进行优化,优化目标如下: