论文标题
迷你模型改编:通过对齐的浅培训有效地将预告额的模型扩展到新语言
Mini-Model Adaptation: Efficiently Extending Pretrained Models to New Languages via Aligned Shallow Training
论文作者
论文摘要
先前的工作表明,可以通过学习一组新的嵌入方式,同时保持变压器的身体冻结,从而将经过验证的蒙版语言模型(MLM)扩展到新语言。尽管学习了一小部分参数,但这种方法并不是计算效率,因为训练新嵌入需要对整个模型进行全面和向后传递。我们提出了Mini-Model Adaptation,这是一种计算效率的替代方案,该替代方案从大型模型参数的一部分中构建浅微型模型。然后,可以在迷你模型上有效训练新的特定于语言的嵌入,并插入对齐的大型型号进行快速跨语性转移。我们探索了学习迷你模型的两种方法:Minijoint,它们使用单个变压器在中间层的次级MLM头部共同预处理主要模型和迷你模型; Minipost我们是从常规审慎的型号开始的,它通过提取和冷冻几层来构建迷你模型,并在顶部学习少量参数。 XNLI,MLQA和PAWS-X的实验表明,使用平均2.3倍的计算较小的标准方法的性能与标准方法的性能相匹配。
Prior work shows that it is possible to expand pretrained Masked Language Models (MLMs) to new languages by learning a new set of embeddings, while keeping the transformer body frozen. Despite learning a small subset of parameters, this approach is not compute-efficient, as training the new embeddings requires a full forward and backward pass over the entire model. We propose mini-model adaptation, a compute-efficient alternative that builds a shallow mini-model from a fraction of a large model's parameters. New language-specific embeddings can then be efficiently trained over the mini-model and plugged into the aligned large model for rapid cross-lingual transfer. We explore two approaches to learn mini-models: MiniJoint, which jointly pretrains the primary model and the mini-model using a single transformer with a secondary MLM head at a middle layer; and MiniPost, where we start from a regular pretrained model, build a mini-model by extracting and freezing a few layers, and learn a small number of parameters on top. Experiments on XNLI, MLQA and PAWS-X show that mini-model adaptation matches the performance of the standard approach using 2.3x less compute on average.