论文标题
在线元学习的可变射击改编
Variable-Shot Adaptation for Online Meta-Learning
论文作者
论文摘要
几乎没有射击的元学习方法可以通过从一组以前的任务中跨静态数据进行元学习来从少量示例中学习新任务的问题。但是,在许多现实世界中,更自然地将问题视为最大程度地减少监督总量的问题之一---学习新任务所需的示例数量以及元学习所需的数据量。可以在顺序学习环境中研究这种公式,其中任务按顺序呈现。在在这种在线环境中研究元学习时,会出现一个关键的问题:在考虑元训练和同时适应时,元学习能否改善样本的复杂性和标准经验风险最小化方法的遗憾?对于具有复杂的双层优化的元学习算法而言,答案尤为明显,可能需要大量的元训练数据。为了回答这个问题,我们扩展了以前的元学习算法,以处理在顺序学习中自然出现的可变示例设置:从一开始就从许多摄像学习到零摄像的学习到最后。在顺序学习问题上,我们发现,与标准监督方法相比,元学习可以解决整体标签较少的整体任务集,并实现更大的累积性能。这些结果表明,元学习是建立学习系统的重要组成部分,这些学习系统不断地学习和改进一系列问题。
Few-shot meta-learning methods consider the problem of learning new tasks from a small, fixed number of examples, by meta-learning across static data from a set of previous tasks. However, in many real world settings, it is more natural to view the problem as one of minimizing the total amount of supervision --- both the number of examples needed to learn a new task and the amount of data needed for meta-learning. Such a formulation can be studied in a sequential learning setting, where tasks are presented in sequence. When studying meta-learning in this online setting, a critical question arises: can meta-learning improve over the sample complexity and regret of standard empirical risk minimization methods, when considering both meta-training and adaptation together? The answer is particularly non-obvious for meta-learning algorithms with complex bi-level optimizations that may demand large amounts of meta-training data. To answer this question, we extend previous meta-learning algorithms to handle the variable-shot settings that naturally arise in sequential learning: from many-shot learning at the start, to zero-shot learning towards the end. On sequential learning problems, we find that meta-learning solves the full task set with fewer overall labels and achieves greater cumulative performance, compared to standard supervised methods. These results suggest that meta-learning is an important ingredient for building learning systems that continuously learn and improve over a sequence of problems.