| | https://openreview.net/forum?id=iedYJm92o0a.</ref>。最近的一种称为思维链(Chain-of-Thought, CoT)提示的提示策略,能够引导模型在给出最终答案之前生成一系列中间步骤,最终帮助模型解决问题<ref name="chain-of-thought" /><ref name="Cobbe2021">Cobbe, K., Kosaraju, V., Bavarian, M., Hilton, J., Nakano, R., Hesse, C., & Schulman, J. Training verifiers to solve math word problems. arXiv preprint arXiv:2110.14168, 2021. URL https://arxiv.org/abs/2110.14168.</ref><ref name="Suzgun2022>Suzgun, M., Scales, N., Scharli, N., Gehrmann, S., Tay, Y., Chung, H.Y., Chowdhery, A., Le, Q.V., Chi, E.H., Zhou, D., & Wei, J. Challenging BIG-Bench tasks and whether chain-of-thought can solve them. arXiv preprint arXiv:2210.09261, 2022. URL https://arxiv.org/abs/2210.09261.</ref>。正如下图A所示,当规模扩大到10<sup>23</sup>训练 FLOPs(约100B参数)时,思维链提示超越了没有中间步骤的标准提示。当在少样本提示后附加解释来增强提示时,也观察到了类似的能力提升涌现<ref name="Lampinen2022年">Lampinen, A.k., Dasgupta, I., Chan, S. C.Y., Matthewson, K., Tessler, M.H., Creswell, A., McClelland, J.L., Wang, J.X., & Hill, F. Can language models learn from explanations in context? Findings of EMNLP, 2022. URL https://arxiv.org/abs/2204.02329.</ref>。 | | https://openreview.net/forum?id=iedYJm92o0a.</ref>。最近的一种称为思维链(Chain-of-Thought, CoT)提示的提示策略,能够引导模型在给出最终答案之前生成一系列中间步骤,最终帮助模型解决问题<ref name="chain-of-thought" /><ref name="Cobbe2021">Cobbe, K., Kosaraju, V., Bavarian, M., Hilton, J., Nakano, R., Hesse, C., & Schulman, J. Training verifiers to solve math word problems. arXiv preprint arXiv:2110.14168, 2021. URL https://arxiv.org/abs/2110.14168.</ref><ref name="Suzgun2022>Suzgun, M., Scales, N., Scharli, N., Gehrmann, S., Tay, Y., Chung, H.Y., Chowdhery, A., Le, Q.V., Chi, E.H., Zhou, D., & Wei, J. Challenging BIG-Bench tasks and whether chain-of-thought can solve them. arXiv preprint arXiv:2210.09261, 2022. URL https://arxiv.org/abs/2210.09261.</ref>。正如下图A所示,当规模扩大到10<sup>23</sup>训练 FLOPs(约100B参数)时,思维链提示超越了没有中间步骤的标准提示。当在少样本提示后附加解释来增强提示时,也观察到了类似的能力提升涌现<ref name="Lampinen2022年">Lampinen, A.k., Dasgupta, I., Chan, S. C.Y., Matthewson, K., Tessler, M.H., Creswell, A., McClelland, J.L., Wang, J.X., & Hill, F. Can language models learn from explanations in context? Findings of EMNLP, 2022. URL https://arxiv.org/abs/2204.02329.</ref>。 |
| | * '''指令跟随(Instruction Following)'''. 另一种日益增多的研究旨在使语言模型通过阅读一段对于任务的描述来执行新任务,但不给出少量样本示例。通过在混合了各种指令式任务的数据上进行微调,语言模型已被证明能够进行适当的响应<ref name="Finetuned" /><ref name="Ouyang2022">Ouyang,L., Wu, J., Jiang, X., Almeida, D., Wainwright, C.L., Mishkin, P., Zhang, C., Agarwal, S., Slama, K., Ray, A. et al. Training language models to follow instructions with human feedback. arXiv preprint arXiv:2203.02155, 2022. URL https://arxiv.org/abs/2203.02155.</ref><ref name="Sanh2022">Sanh, V., Webson, A., Raffel, C., Bach, S., Sutawika, L., Alyafeai, Z., Chaffin, A., Stiegler, A., Scao, T.L., Raja, A. et al. Multitask prompted training enables zero-shot task generalization. ICLR, 2022. URL https://openreview.net/forum?id=9Vrb9D0WI4.</ref><ref name="Chung2022">Chung, H.W., Hou, L., Longpre, S., Zoph, B., Tay, Y., Fedus, W., Li, E., Wang, X., Dehghani, M., Brahma, S. et al. Scaling instruction-finetuned language models. arXiv preprint arXiv:2210.11416, 2022. URL https://arxiv.org/abs/2210.11416.</ref>。如图B所示,这种指令微调技术对于训练FLOPs为7×10<sup>21</sup>(8B参数)或更小的模型有损害,只有当规模扩大到10<sup>23</sup>训练FLOPs(约100B参数)时,才会提高模型能力<ref name="Finetuned" />(尽管有研究者随后发现,这种指令跟随的行为也可以通过微调更小的 encoder-decoder T5 模型来诱导<ref name="Sanh2022" />)。 | | * '''指令跟随(Instruction Following)'''. 另一种日益增多的研究旨在使语言模型通过阅读一段对于任务的描述来执行新任务,但不给出少量样本示例。通过在混合了各种指令式任务的数据上进行微调,语言模型已被证明能够进行适当的响应<ref name="Finetuned" /><ref name="Ouyang2022">Ouyang,L., Wu, J., Jiang, X., Almeida, D., Wainwright, C.L., Mishkin, P., Zhang, C., Agarwal, S., Slama, K., Ray, A. et al. Training language models to follow instructions with human feedback. arXiv preprint arXiv:2203.02155, 2022. URL https://arxiv.org/abs/2203.02155.</ref><ref name="Sanh2022">Sanh, V., Webson, A., Raffel, C., Bach, S., Sutawika, L., Alyafeai, Z., Chaffin, A., Stiegler, A., Scao, T.L., Raja, A. et al. Multitask prompted training enables zero-shot task generalization. ICLR, 2022. URL https://openreview.net/forum?id=9Vrb9D0WI4.</ref><ref name="Chung2022">Chung, H.W., Hou, L., Longpre, S., Zoph, B., Tay, Y., Fedus, W., Li, E., Wang, X., Dehghani, M., Brahma, S. et al. Scaling instruction-finetuned language models. arXiv preprint arXiv:2210.11416, 2022. URL https://arxiv.org/abs/2210.11416.</ref>。如图B所示,这种指令微调技术对于训练FLOPs为7×10<sup>21</sup>(8B参数)或更小的模型有损害,只有当规模扩大到10<sup>23</sup>训练FLOPs(约100B参数)时,才会提高模型能力<ref name="Finetuned" />(尽管有研究者随后发现,这种指令跟随的行为也可以通过微调更小的 encoder-decoder T5 模型来诱导<ref name="Sanh2022" />)。 |
| | * '''模型校准(Calibration).''' 模型校准能够衡量模型预测其回答正确率的能力,代表了模型回答问题的可靠程度。举个例子,当模型给出回答A的采样概率是90%时,说明它有九成把握自己做对了,而如果实际情况真的是10次问题中有9次做对了,说明模型有很高的校准能力。研究者使用平均校准误差(Expected Calibration Error,ECE)来度量模型校准能力的大小。有研究者比较了两种衡量校准的情境<ref name=":Kadavath2022">Kadavath, S., Conerly, T., Askell, A., Henighan, T., Drain, E., Perez, E., Schiefer, N., Hatfield-Dodds Z., et al. (2022) Language Models (Mostly) Know What They Know.(arXiv:2207.05221). arXiv. https://arxiv.org/abs/2207.05221</ref>:一种是T/F判断题,在提示中会给出一段陈述,让模型给出“正确”或者“错误”的回答。另一种则是单选题,让大模型直接在多个选项中选择正确的答案。如图D所示,在二选一的情境下,模型在大约3×10<sup>23</sup>训练FLOPs(52B参数)的时候出现了涌现现象,而单选题的情境下模型校准能力一直以幂律的形式平滑增长。 | | * '''模型校准(Calibration).''' 模型校准能够衡量模型预测其回答正确率的能力,代表了模型回答问题的可靠程度。举个例子,当模型给出回答A的采样概率是90%时,说明它有九成把握自己做对了,而如果实际情况真的是10次问题中有9次做对了,说明模型有很高的校准能力。研究者使用平均校准误差(Expected Calibration Error,ECE)来度量模型校准能力的大小。有研究者比较了两种衡量校准的情境<ref name=":Kadavath2022">Kadavath, S., Conerly, T., Askell, A., Henighan, T., Drain, E., Perez, E., Schiefer, N., Hatfield-Dodds Z., et al. (2022) Language Models (Mostly) Know What They Know.(arXiv:2207.05221). arXiv. https://arxiv.org/abs/2207.05221</ref>:一种是T/F判断题,在提示中会给出一段陈述,让模型给出“正确”或者“错误”的回答。另一种则是单选题,让大模型直接在多个选项中选择正确的答案。如图D所示,在二选一的情境下,模型在大约3×10<sup>23</sup>训练FLOPs(52B参数)的时候出现了涌现现象,而单选题的情境下模型校准能力一直以幂律的形式平滑增长。 |