Recent NLP models have the great ability to generalise `zero-shot' to new tasks using only an instruction as guidance. However, these approaches usually repeat their instructions with every input, requiring costly reprocessing of lengthy instructions for every inference example. To alleviate this, we introduce Hypernetworks for INstruction Tuning (HINT), which convert task instructions and examples using a pretrained text encoder into parameter-efficient modules inserted into an underlying model, eliminating the need to include instructions in the model input. Compared to prior approaches that concatenate instructions with every input instance, we find that HINT models are significantly more compute-efficient and consistently outperform these approaches for a given inference budget.
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几乎没有射击的内在学习(ICL)使预训练的语言模型能够通过为输入的一部分提供少量的培训示例来执行以前的任务,而无需任何基于梯度的培训。 ICL会产生大量的计算,内存和存储成本,因为它每次进行预测时都涉及处理所有培训示例。参数有效的微调(PEFT)(例如,适配器模块,提示调谐,稀疏更新方法等)提供了替代范式,其中训练了一组少量参数以启用模型来执行新任务。在本文中,我们严格地比较了几个ICL和PEFT,并证明后者提供了更好的准确性,并大大降低了计算成本。在此过程中,我们引入了一种称为(IA)$^3 $的新PEFT方法,该方法通过学习的向量来扩展激活,从而获得更强的性能,同时仅引入相对少量的新参数。我们还提出了一个基于称为T-FEW的T0模型的简单食谱,可以将其应用于新任务,而无需特定于任务的调整或修改。我们通过将T-FEW应用于木筏基准,首次实现超人性能,并以6%的绝对性能优于最先进的方法来验证T-FEW对完全看不见的任务的有效性。我们实验中使用的所有代码均可公开使用。
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The BLOOM model is a large open-source multilingual language model capable of zero-shot learning, but its pretraining was limited to 46 languages. To improve its zero-shot performance on unseen languages, it is desirable to adapt BLOOM, but previous works have only explored adapting small language models. In this work, we apply existing language adaptation strategies to BLOOM and benchmark its zero-shot prompting performance on eight new languages. We find language adaptation to be effective at improving zero-shot performance in new languages. Surprisingly, adapter-based finetuning is more effective than continued pretraining for large models. In addition, we discover that prompting performance is not significantly affected by language specifics, such as the writing system. It is primarily determined by the size of the language adaptation data. We also add new languages to BLOOMZ, which is a multitask finetuned version of BLOOM capable of following task instructions zero-shot. We find including a new language in the multitask fine-tuning mixture to be the most effective method to teach BLOOMZ a new language. We conclude that with sufficient training data language adaptation can generalize well to diverse languages. Our code is available at \url{https://github.com/bigscience-workshop/multilingual-modeling/}.
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及时调整是以参数有效的方式对预训练的预训练语言模型的新范式。在这里,我们探讨了超级核武器的使用来产生超预价:我们提出了HyperPrompt,这是一种用于迅速基于变形金刚自我注意的任务调节的新型体系结构。超预要是通过超网络通过一代人来学习的端到端。 HyperPrompt允许网络学习特定于任务的功能地图,其中超预告是要参与的查询的任务全局记忆,同时启用了任务之间的灵活信息共享。我们表明,HyperPrompt与强大的多任务学习基线具有竞争力,其额外的任务条件参数的$ 0.14 \%$ $ \%,实现了出色的参数和计算效率。通过广泛的经验实验,我们证明,超级启示可以比强大的T5多任务学习基准和参数效率高效的适配器变体获得卓越的性能,包括及时调整和SuplyFormer ++在许多模型尺寸的自然语言理解胶水和SuperGrue的基准上。
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Language models trained on massive prompted multitask datasets like T0 (Sanh et al., 2021) or FLAN (Wei et al., 2021a) can generalize to tasks unseen during training. We show that training on a carefully chosen subset of instances can outperform training on all available data on a variety of datasets. We assume access to a small number (250--1000) of unlabeled target task instances, select their nearest neighbors from a pool of multitask data, and use the retrieved data to train target task-specific models. Our method is more data-efficient than training a single multitask model, while still outperforming it by large margins. We evaluate across a diverse set of tasks not in the multitask pool we retrieve from, including those used to evaluate T0 and additional complex tasks including legal and scientific document QA. We retrieve small subsets of P3 (the collection of prompted datasets from which T0's training data was sampled) and finetune T5 models that outperform the 3-billion parameter variant of T0 (T0-3B) by 3--30% on 12 out of 14 evaluation datasets while using at most 2% of the data used to train T0-3B. These models also provide a better initialization than T0-3B for few-shot finetuning on target-task data, as shown by a 2--23% relative improvement over few-shot finetuned T0-3B models on 8 datasets. Our code is available at https://github.com/allenai/data-efficient-finetuning.
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This work introduces a new multi-task, parameter-efficient language model (LM) tuning method that learns to transfer knowledge across different tasks via a mixture of soft prompts-small prefix embedding vectors pre-trained for different tasks. Our method, called ATTEMPT (ATTEntional Mixtures of Prompt Tuning), obtains source prompts as encodings of large-scale source tasks into a small number of parameters and trains an attention module to interpolate the source prompts and a newly initialized target prompt for every instance in the target task. During training, only the target task prompt and the attention weights, which are shared between tasks in multi-task training, are updated, while the original LM and source prompts are intact. ATTEMPT is highly parameter-efficient (e.g., updates 2,300 times fewer parameters than full fine-tuning) while achieving high task performance using knowledge from high-resource tasks. Moreover, it is modular using pre-trained soft prompts, and can flexibly add or remove source prompts for effective knowledge transfer. Our experimental results across 21 diverse NLP datasets show that ATTEMPT significantly outperforms prompt tuning and outperforms or matches fully fine-tuned or other parameter-efficient tuning approaches that use over ten times more parameters. Finally, ATTEMPT outperforms previous work in few-shot learning settings.
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本文探讨了提高语言模型的零次学习能力的简单方法。我们表明,指令调整 - 通过对说明书中所述的任务集合微调语言模型 - 大幅提升零射门上看不见任务中的表现。我们采取预训练的语言模型和指令调整它通过自然语言指令模板语言表达了60NLP任务137B参数。我们评估这种指令调整模型,我们称之为FLAN,在看不见的任务类型。FLAN显着改善其未修饰的对应的性能和超过25的20个任务,我们评估零射门175BGPT-3。FLAN甚至GPT-3通过在安利,RTE,BoolQ,AI2-ARC,OpenbookQA和StoryCloze大比分胜过几拍。消融研究显示任务和模型的规模,这个数字是指令调整取得成功的关键组成部分。
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及时的调整已成为模型调整的新范式,它在自然语言预处理甚至预处理方面都取得了成功。在这项工作中,我们探讨了迅速调整到多模式预处理的转移,重点是生成的多模式预审预周化模型,而不是对比度。具体而言,我们实施了迅速调整统一的序列到序列预测模型适应理解和生成任务。实验结果表明,轻重量提示调整可以通过填充并超过其他轻量调整方法来实现可比的性能。此外,与固定模型相比,迅速调整的模型表明了针对对抗性攻击的鲁棒性。我们进一步确定,实验因素,包括及时长度,及时的深度和重新聚集化,对模型性能产生了很大的影响,因此我们从经验上为迅速调整的设置提供了建议。尽管有观察到的优势,但我们仍然在迅速调整中发现了一些局限性,我们相应地指出了未来研究的方向。代码可在\ url {https://github.com/ofa-sys/ofa}中获得
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Finetuning language models on a collection of datasets phrased as instructions has been shown to improve model performance and generalization to unseen tasks. In this paper we explore instruction finetuning with a particular focus on (1) scaling the number of tasks, (2) scaling the model size, and (3) finetuning on chain-of-thought data. We find that instruction finetuning with the above aspects dramatically improves performance on a variety of model classes (PaLM, T5, U-PaLM), prompting setups (zero-shot, few-shot, CoT), and evaluation benchmarks (MMLU, BBH, TyDiQA, MGSM, open-ended generation). For instance, Flan-PaLM 540B instruction-finetuned on 1.8K tasks outperforms PALM 540B by a large margin (+9.4% on average). Flan-PaLM 540B achieves state-of-the-art performance on several benchmarks, such as 75.2% on five-shot MMLU. We also publicly release Flan-T5 checkpoints, which achieve strong few-shot performance even compared to much larger models, such as PaLM 62B. Overall, instruction finetuning is a general method for improving the performance and usability of pretrained language models.
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最近的作品表明,将提示附加到输入方面有效,可以在调节语言模型(LM)上执行特定任务。但是,提示在推理过程中始终包含在输入文本中,从而产生了实质性的计算和内存开销。同样,目前尚无直接使用提示的方法,其提示比LMS的最大输入长度更长,而不会在推理过程中产生额外费用。我们提出了提示注射(PI),这是一种将提示注入LM参数的新型公式,是将固定提示附加到输入的有效替代方案。我们表明,在有固定提示的情况下,PI的总拖鞋的效率可能比以前的方法高280倍。我们进一步探讨了PI的方法论,并通过角色依赖的对话,语义解析和零射击学习显示了有希望的结果。通过这些探索,我们表明PI可以成为调节语言模型的有前途的方向,尤其是在具有长长和固定提示的情况下。
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In this work, we explore "prompt tuning," a simple yet effective mechanism for learning "soft prompts" to condition frozen language models to perform specific downstream tasks. Unlike the discrete text prompts used by GPT-3, soft prompts are learned through backpropagation and can be tuned to incorporate signals from any number of labeled examples. Our end-to-end learned approach outperforms GPT-3's few-shot learning by a large margin. More remarkably, through ablations on model size using T5, we show that prompt tuning becomes more competitive with scale: as models exceed billions of parameters, our method "closes the gap" and matches the strong performance of model tuning (where all model weights are tuned). This finding is especially relevant because large models are costly to share and serve and the ability to reuse one frozen model for multiple downstream tasks can ease this burden. Our method can be seen as a simplification of the recently proposed "prefix tuning" of Li and Liang (2021) and we provide a comparison to this and other similar approaches. Finally, we show that conditioning a frozen model with soft prompts confers benefits in robustness to domain transfer and enables efficient "prompt ensembling." * Work done as a Google AI Resident.
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Multilingual machine translation suffers from negative interference across languages. A common solution is to relax parameter sharing with language-specific modules like adapters. However, adapters of related languages are unable to transfer information, and their total number of parameters becomes prohibitively expensive as the number of languages grows. In this work, we overcome these drawbacks using hyper-adapters -- hyper-networks that generate adapters from language and layer embeddings. While past work had poor results when scaling hyper-networks, we propose a rescaling fix that significantly improves convergence and enables training larger hyper-networks. We find that hyper-adapters are more parameter efficient than regular adapters, reaching the same performance with up to 12 times less parameters. When using the same number of parameters and FLOPS, our approach consistently outperforms regular adapters. Also, hyper-adapters converge faster than alternative approaches and scale better than regular dense networks. Our analysis shows that hyper-adapters learn to encode language relatedness, enabling positive transfer across languages.
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Pre-trained large language models can efficiently interpolate human-written prompts in a natural way. Multitask prompted learning can help generalization through a diverse set of tasks at once, thus enhancing the potential for more effective downstream fine-tuning. To perform efficient multitask-inference in the same batch, parameter-efficient fine-tuning methods such as prompt tuning have been proposed. However, the existing prompt tuning methods may lack generalization. We propose SPT, a semi-parametric prompt tuning method for multitask prompted learning. The novel component of SPT is a memory bank from where memory prompts are retrieved based on discrete prompts. Extensive experiments, such as (i) fine-tuning a full language model with SPT on 31 different tasks from 8 different domains and evaluating zero-shot generalization on 9 heldout datasets under 5 NLP task categories and (ii) pretraining SPT on the GLUE datasets and evaluating fine-tuning on the SuperGLUE datasets, demonstrate effectiveness of SPT.
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通过微调将大规模的预训练语言模型适应下游任务是实现NLP基准测试最先进性能的标准方法。然而,微调具有数百万或数十亿个参数的所有重量模型是对低资源设置中不稳定的采样低效,并且浪费,因为它需要为每个任务存储模型的单独副本。最近的工作已经开发了参数高效的微调方法,但这些方法仍然需要相对大量的参数或表现不足标准微调。在这项工作中,我们提出了一种特殊调整大型语言模型的方法,其在任务性能和比率参数之间具有更好的权衡的方法,而不是比上事先工作。 Compacter通过构建适配器,低级优化和参数化超复分乘法层的思想之上来实现这一目标。具体地,Compacter将特定于特定的权重矩阵插入到预估计模型的权重中,这些权重被有效地计算为共享的“慢速”权重和“快速”等级 - 每个Compacter层定义的矩阵之间的矩阵产品的总和。仅通过培训0.047%的预磨料模型的参数,Compacter会在胶水上标准微调和胜过标准微调的标准微调和低资源设置。我们的代码在〜\ url {https://github.com/rabeehk/compacter}上公开使用。
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在这项工作中,我们证明了多种语的大规模序列到序列(SEQ2SEQ)模型,该模型是通过Denoising和因果语言建模(CLM)任务的混合物进行训练的,比仅解码器模型更有效地进行了效率的学习者在各种任务上。特别是,我们培训了一个名为Alexa教师模型(Alexatm 20b)的200亿个参数多语言SEQ2SEQ模型,并表明它在1-Shot摘要任务上实现了最先进的(SOTA)性能,超过了更大的540B PALM DOPODER模型。 Alexatm 20b还可以在1-Shot Machine翻译中实现SOTA,尤其是对于低资源语言,几乎所有语言对(阿拉伯语,英语,法语,德语,德语,印地语,意大利语,日语,以及flores-101数据集上的泰卢固语)。我们还显示了零拍设置,AlexATM 20B在SuperGlue和SqueadV2数据集上的表现优于GPT3(175B),并在XNLI,XCOPA,PAWS-X和XWINOGRAD等多语言任务上提供SOTA性能。总体而言,我们的结果为SEQ2SEQ模型提供了一个令人信服的案例,作为大型语言模型(LLM)培训的仅解码器模型的强大替代方法。
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Instruction tuning enables pretrained language models to perform new tasks from inference-time natural language descriptions. These approaches rely on vast amounts of human supervision in the form of crowdsourced datasets or user interactions. In this work, we introduce Unnatural Instructions: a large dataset of creative and diverse instructions, collected with virtually no human labor. We collect 64,000 examples by prompting a language model with three seed examples of instructions and eliciting a fourth. This set is then expanded by prompting the model to rephrase each instruction, creating a total of approximately 240,000 examples of instructions, inputs, and outputs. Experiments show that despite containing a fair amount of noise, training on Unnatural Instructions rivals the effectiveness of training on open-source manually-curated datasets, surpassing the performance of models such as T0++ and Tk-Instruct across various benchmarks. These results demonstrate the potential of model-generated data as a cost-effective alternative to crowdsourcing for dataset expansion and diversification.
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基础模型由于在广泛的下游应用中的有效性而受到了很多关注。尽管在体系结构方面存在很大的融合,但大多数审慎的模型通常仍用于特定任务或模式。在这项工作中,我们建议将语言模型用作各种基础模型的通用接口。一系列预处理的编码者感知到了多种方式(例如视觉和语言),并与扮演通用任务层角色的语言模型对接。我们提出了一个半伴侣的语言建模目标,以共同确定界面和模块化编码器。我们从因果关系和非因果建模中涵盖了优势和能力,从而结合了两个世界的最佳状态。具体而言,所提出的方法不仅从因果语言建模中继承了内在学习和开放式生成的能力,而且由于双向编码器而有利于填补。更重要的是,我们的方法无缝地解锁了上述功能的组合,例如,通过填充编码器启用了文本学习或指导。各种仅语言和视觉语言基准的实验结果表明,我们的模型表现优于或与鉴定,零弹性概括和几乎没有的学习的专业模型竞争。
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Meta-training, which fine-tunes the language model (LM) on various downstream tasks by maximizing the likelihood of the target label given the task instruction and input instance, has improved the zero-shot task generalization performance. However, meta-trained LMs still struggle to generalize to challenging tasks containing novel labels unseen during meta-training. In this paper, we propose Flipped Learning, an alternative method of meta-training which trains the LM to generate the task instruction given the input instance and label. During inference, the LM trained with Flipped Learning, referred to as Flipped, selects the label option that is most likely to generate the task instruction. On 14 tasks of the BIG-bench benchmark, the 11B-sized Flipped outperforms zero-shot T0-11B and even a 16 times larger 3-shot GPT-3 (175B) on average by 8.4% and 9.7% points, respectively. Flipped gives particularly large improvements on tasks with unseen labels, outperforming T0-11B by up to +20% average F1 score. This indicates that the strong task generalization of Flipped comes from improved generalization to novel labels. We release our code at https://github.com/seonghyeonye/Flipped-Learning.
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大型语言模型(例如GPT-3(Brown等,2020)可以执行任意任务,而无需在仅使用少数标签示例的提示之后进行微调。可以将任意任务重新构成自然语言提示,并且可以要求语言模型生成完成,并以称为基于及时的学习的范式间接执行该任务。迄今为止,主要针对单向语言模型证明了新兴迅速的学习能力。但是,预先培训的双向语言模型(例如蒙版语言建模)为转移学习提供了更强大的学习表示。这激发了促使双向模型的可能性,但是它们的预训练目标使它们与现有的提示范式不相容。我们提出SAP(顺序自动回旋提示),该技术可以使双向模型提示。利用机器翻译任务作为案例研究,我们提示了带有SAP的双向MT5模型(Xue等,2021),并演示其少量拍摄和零照片的翻译优于GPT-3等单向模型的几个单拍翻译和XGLM(Lin等,2021),尽管MT5的参数减少了约50%。我们进一步表明SAP对问题的回答和摘要有效。我们的结果首次表明基于及时的学习是更广泛的语言模型的新兴属性,而不仅仅是单向模型。
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Parameter-efficient fine-tuning (PEFT) methods can adapt large language models to downstream tasks by training a small amount of newly added parameters. In multi-task settings, PEFT adapters typically train on each task independently, inhibiting transfer across tasks, or on the concatenation of all tasks, which can lead to negative interference. To address this, Polytropon (Ponti et al.) jointly learns an inventory of PEFT adapters and a routing function to share variable-size sets of adapters across tasks. Subsequently, adapters can be re-combined and fine-tuned on novel tasks even with limited data. In this paper, we investigate to what extent the ability to control which adapters are active for each task leads to sample-efficient generalization. Thus, we propose less expressive variants where we perform weighted averaging of the adapters before few-shot adaptation (Poly-mu) instead of learning a routing function. Moreover, we introduce more expressive variants where finer-grained task-adapter allocation is learned through a multi-head routing function (Poly-S). We test these variants on three separate benchmarks for multi-task learning. We find that Poly-S achieves gains on all three (up to 5.3 points on average) over strong baselines, while incurring a negligible additional cost in parameter count. In particular, we find that instruction tuning, where models are fully fine-tuned on natural language instructions for each task, is inferior to modular methods such as Polytropon and our proposed variants.
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