Large pre-trained language models have recently enabled open-ended generation frameworks (e.g., prompt-to-text NLG) to tackle a variety of tasks going beyond the traditional data-to-text generation. While this framework is more general, it is under-specified and often leads to a lack of controllability restricting their real-world usage. We propose a new grounded keys-to-text generation task: the task is to generate a factual description about an entity given a set of guiding keys, and grounding passages. To address this task, we introduce a new dataset, called EntDeGen. Inspired by recent QA-based evaluation measures, we propose an automatic metric, MAFE, for factual correctness of generated descriptions. Our EntDescriptor model is equipped with strong rankers to fetch helpful passages and generate entity descriptions. Experimental result shows a good correlation (60.14) between our proposed metric and human judgments of factuality. Our rankers significantly improved the factual correctness of generated descriptions (15.95% and 34.51% relative gains in recall and precision). Finally, our ablation study highlights the benefit of combining keys and groundings.
translated by 谷歌翻译
我们介绍了Godel(接地开放对话语言模型),这是对话框的大型预训练的语言模型。与诸如Dialogpt之类的早期模型相比,Godel利用了一个新的扎根预训练阶段,旨在更好地支持将Godel适应广泛的下游对话框任务,这些任务需要当前对话外部的信息(例如,数据库或文档)到产生良好的回应。针对一系列基准测试的实验,这些基准涵盖了面向任务的对话框,对话质量质量检查和接地的开放式对话框,表明Godel在几次以上的微调设置中优于最先进的预训练的对话模型,就人类和自动评估。我们评估方法的一个新颖特征是引入了一个效用概念,该概念除了其交流特征(内在评估)外,还评估了响应的有用性(外部评估)。我们表明,外部评估提供了改进的通道间一致性和与自动指标的相关性。代码和数据处理脚本公开可用。
translated by 谷歌翻译
已显示自动回归神经序列模型在文本生成任务中有效。然而,它们的左右解码顺序可防止产生并行化。插入变压器(Stern等,2019)是一种有吸引力的替代方案,允许在单一代币上输出多个令牌。然而,由于绝对位置编码和基于插入的生成方案的不兼容,需要刷新每个步骤的所生成的部分假设中的每个令牌的编码,这可能是昂贵的。我们设计一种用于分数位置编码(FPE)的插入变压器的新型增量位置编码方案,其允许重用在先前步骤中计算的表示。关于各种语言生成任务的实证研究证明了FPE的有效性,这导致批量解码减少浮点操作和潜伏期改善。
translated by 谷歌翻译
最近的大规模预训练的进步,例如GPT-3允许从给定提示生成看似高质量的文本。然而,这种一代系统经常遭受幻觉的事实问题,并且本身并不是旨在包含有用的外部信息。接地的代表似乎提供了补救措施,但他们的培训通常依赖于提供信息相关文件的很少可用的并行数据。我们提出了一个框架,通过在语言模型信号上共同训练接地的发生器和文档检索来缓解这种数据约束。该模型学会奖励具有生成中最高效用的文档的检索,并用专家混合(MOE)合并来术语术,以产生后续文本。我们证明,发电机和猎犬都可以利用这种联合培训,协同作用,以生产散文和对话一代中的更多信息和相关文本。
translated by 谷歌翻译
We present a large, tunable neural conversational response generation model, DIALOGPT (dialogue generative pre-trained transformer). Trained on 147M conversation-like exchanges extracted from Reddit comment chains over a period spanning from 2005 through 2017, DialoGPT extends the Hugging Face PyTorch transformer to attain a performance close to human both in terms of automatic and human evaluation in single-turn dialogue settings. We show that conversational systems that leverage DialoGPT generate more relevant, contentful and context-consistent responses than strong baseline systems. The pre-trained model and training pipeline are publicly released to facilitate research into neural response generation and the development of more intelligent opendomain dialogue systems.
translated by 谷歌翻译
Sequence-to-sequence neural network models for generation of conversational responses tend to generate safe, commonplace responses (e.g., I don't know) regardless of the input. We suggest that the traditional objective function, i.e., the likelihood of output (response) given input (message) is unsuited to response generation tasks. Instead we propose using Maximum Mutual Information (MMI) as the objective function in neural models. Experimental results demonstrate that the proposed MMI models produce more diverse, interesting, and appropriate responses, yielding substantive gains in BLEU scores on two conversational datasets and in human evaluations. Input: What are you doing? −0.86 I don't know. −1.09 Get out of here. −1.03 I don't know! −1.09 I'm going home. −1.06 Nothing. −1.09 Oh my god! −1.09 Get out of the way. −1.10 I'm talking to you. Input: what is your name? −0.91 I don't know. ... −0.92 I don't know! −1.55 My name is Robert. −0.92 I don't know, sir. −1.58 My name is John. −0.97 Oh, my god! −1.59 My name's John. Input: How old are you? −0.79 I don't know. ... −1.06 I'm fine.−1.64 Twenty-five. −1.17 I'm all right.−1.66 Five. −1.17 I'm not sure.−1.71 Eight.
translated by 谷歌翻译
An oft-cited open problem of federated learning is the existence of data heterogeneity at the clients. One pathway to understanding the drastic accuracy drop in federated learning is by scrutinizing the behavior of the clients' deep models on data with different levels of "difficulty", which has been left unaddressed. In this paper, we investigate a different and rarely studied dimension of FL: ordered learning. Specifically, we aim to investigate how ordered learning principles can contribute to alleviating the heterogeneity effects in FL. We present theoretical analysis and conduct extensive empirical studies on the efficacy of orderings spanning three kinds of learning: curriculum, anti-curriculum, and random curriculum. We find that curriculum learning largely alleviates non-IIDness. Interestingly, the more disparate the data distributions across clients the more they benefit from ordered learning. We provide analysis explaining this phenomenon, specifically indicating how curriculum training appears to make the objective landscape progressively less convex, suggesting fast converging iterations at the beginning of the training procedure. We derive quantitative results of convergence for both convex and nonconvex objectives by modeling the curriculum training on federated devices as local SGD with locally biased stochastic gradients. Also, inspired by ordered learning, we propose a novel client selection technique that benefits from the real-world disparity in the clients. Our proposed approach to client selection has a synergic effect when applied together with ordered learning in FL.
translated by 谷歌翻译
Nine language-vision AI models trained on web scrapes with the Contrastive Language-Image Pretraining (CLIP) objective are evaluated for evidence of a bias studied by psychologists: the sexual objectification of girls and women, which occurs when a person's human characteristics are disregarded and the person is treated as a body or a collection of body parts. A first experiment uses standardized images of women from the Sexual OBjectification and EMotion Database, and finds that, commensurate with prior research in psychology, human characteristics are disassociated from images of objectified women: the model's recognition of emotional state is mediated by whether the subject is fully or partially clothed. Embedding association tests (EATs) return significant effect sizes for both anger (d >.8) and sadness (d >.5). A second experiment measures the effect in a representative application: an automatic image captioner (Antarctic Captions) includes words denoting emotion less than 50% as often for images of partially clothed women than for images of fully clothed women. A third experiment finds that images of female professionals (scientists, doctors, executives) are likely to be associated with sexual descriptions relative to images of male professionals. A fourth experiment shows that a prompt of "a [age] year old girl" generates sexualized images (as determined by an NSFW classifier) up to 73% of the time for VQGAN-CLIP (age 17), and up to 40% of the time for Stable Diffusion (ages 14 and 18); the corresponding rate for boys never surpasses 9%. The evidence indicates that language-vision AI models trained on automatically collected web scrapes learn biases of sexual objectification, which propagate to downstream applications.
translated by 谷歌翻译
Pre-trained language models have been successful in natural language generation (NLG) tasks. While various decoding methods have been employed, they often produce suboptimal results. We first present an empirical analysis of three NLG tasks: summarization, machine translation, and constrained text generation. We found that selecting the best output from the results of multiple decoding methods can significantly improve performance. To further improve reranking for NLG tasks, we proposed a novel method, \textsc{PairReranker}, which uses a single encoder and a pairwise loss function to jointly encode a source input and a pair of candidates and compare them. Experiments on three NLG tasks demonstrated the effectiveness and flexibility of \textsc{PairReranker}, showing strong results, compared with previous baselines. In addition, our \textsc{PairReranker} can generalize to significantly improve GPT-3 (text-davinci-003) results (e.g., 24.55\% on CommonGen and 11.35\% on WMT18 zh-en), even though our rerankers are not trained with any GPT-3 candidates.
translated by 谷歌翻译
We study critical systems that allocate scarce resources to satisfy basic needs, such as homeless services that provide housing. These systems often support communities disproportionately affected by systemic racial, gender, or other injustices, so it is crucial to design these systems with fairness considerations in mind. To address this problem, we propose a framework for evaluating fairness in contextual resource allocation systems that is inspired by fairness metrics in machine learning. This framework can be applied to evaluate the fairness properties of a historical policy, as well as to impose constraints in the design of new (counterfactual) allocation policies. Our work culminates with a set of incompatibility results that investigate the interplay between the different fairness metrics we propose. Notably, we demonstrate that: 1) fairness in allocation and fairness in outcomes are usually incompatible; 2) policies that prioritize based on a vulnerability score will usually result in unequal outcomes across groups, even if the score is perfectly calibrated; 3) policies using contextual information beyond what is needed to characterize baseline risk and treatment effects can be fairer in their outcomes than those using just baseline risk and treatment effects; and 4) policies using group status in addition to baseline risk and treatment effects are as fair as possible given all available information. Our framework can help guide the discussion among stakeholders in deciding which fairness metrics to impose when allocating scarce resources.
translated by 谷歌翻译