论文标题
量子统计查询学习
Quantum statistical query learning
论文作者
论文摘要
我们提出了一个名为量子统计学习QSQ模型的学习模型,该模型将Kearns引入的SQ学习模型扩展到量子设置。我们的模型也可以看作是对量子PAC学习模型的限制:在这里,学习者无法直接访问量子示例,但只能获得对它们的测量统计数据的估计。从理论上讲,该模型提供了一个简单而表达的设置,以探索机器学习中量子示例的力量。从实际的角度来看,由于需要更简单的操作,因此QSQ模型中的学习算法对于在近期量子设备上实现更可行。我们证明了有关QSQ学习模型的许多结果。我们首先表明奇偶校验函数,(log n) - juntas和多项式大小的DNF公式在QSQ模型中可以有效地学习,与这些问题很难的经典环境相反。这意味着即使在受限制的量子SQ学习模型中,量子PAC学习的许多优势也可以实现。众所周知,由WSQDIM(C)表示的弱统计查询维度表征了在经典SQ模型中学习概念C类的复杂性。我们表明,log(WSQDIM(c))是QSQ学习的复杂性的下限,此外,对于某些概念类别而言,它也很紧张。此外,我们表明该数量为产品分布下的小偏置量子通信模型提供了强大的下限。最后,我们介绍了私人量子PAC学习的概念,其中量子PAC学习者必须在私有方面私密。我们表明,QSQ模型中的可学习性意味着量子私有PAC模型中的可学习性。此外,我们表明,在私人PAC学习环境中,经典和量子样品的复杂性相等,直至恒定因素。
We propose a learning model called the quantum statistical learning QSQ model, which extends the SQ learning model introduced by Kearns to the quantum setting. Our model can be also seen as a restriction of the quantum PAC learning model: here, the learner does not have direct access to quantum examples, but can only obtain estimates of measurement statistics on them. Theoretically, this model provides a simple yet expressive setting to explore the power of quantum examples in machine learning. From a practical perspective, since simpler operations are required, learning algorithms in the QSQ model are more feasible for implementation on near-term quantum devices. We prove a number of results about the QSQ learning model. We first show that parity functions, (log n)-juntas and polynomial-sized DNF formulas are efficiently learnable in the QSQ model, in contrast to the classical setting where these problems are provably hard. This implies that many of the advantages of quantum PAC learning can be realized even in the more restricted quantum SQ learning model. It is well-known that weak statistical query dimension, denoted by WSQDIM(C), characterizes the complexity of learning a concept class C in the classical SQ model. We show that log(WSQDIM(C)) is a lower bound on the complexity of QSQ learning, and furthermore it is tight for certain concept classes C. Additionally, we show that this quantity provides strong lower bounds for the small-bias quantum communication model under product distributions. Finally, we introduce the notion of private quantum PAC learning, in which a quantum PAC learner is required to be differentially private. We show that learnability in the QSQ model implies learnability in the quantum private PAC model. Additionally, we show that in the private PAC learning setting, the classical and quantum sample complexities are equal, up to constant factors.