论文标题
高维回归问题的统一网络的概率分区
Probabilistic partition of unity networks for high-dimensional regression problems
论文作者
论文摘要
我们在高维回归问题的背景下探讨了Unity网络(PPOU-NET)模型的概率分区,并提出了一个关注自适应维度降低的一般框架。使用提出的框架,目标函数通过低维歧管上的专家模型的混合物近似,其中每个群集都与局部固定学位多项式相关联。我们提出了一种利用期望最大化(EM)算法的培训策略。在培训期间,我们在(i)应用梯度下降以更新DNN系数之间进行交替; (ii)使用从EM算法得出的封闭式公式来更新专家模型参数的混合物。在概率表述下,步骤(ii)承认了令人尴尬的可行加权最小二乘求解的形式。在各种数据维度的数值实验中,PPOU NET始终优于基线完全连接的神经网络。我们还探索了量子计算应用中提出的模型,其中PPOU-NET充当与变异量子电路相关的成本景观的替代模型。
We explore the probabilistic partition of unity network (PPOU-Net) model in the context of high-dimensional regression problems and propose a general framework focusing on adaptive dimensionality reduction. With the proposed framework, the target function is approximated by a mixture of experts model on a low-dimensional manifold, where each cluster is associated with a local fixed-degree polynomial. We present a training strategy that leverages the expectation maximization (EM) algorithm. During the training, we alternate between (i) applying gradient descent to update the DNN coefficients; and (ii) using closed-form formulae derived from the EM algorithm to update the mixture of experts model parameters. Under the probabilistic formulation, step (ii) admits the form of embarrassingly parallelizable weighted least-squares solves. The PPOU-Nets consistently outperform the baseline fully-connected neural networks of comparable sizes in numerical experiments of various data dimensions. We also explore the proposed model in applications of quantum computing, where the PPOU-Nets act as surrogate models for cost landscapes associated with variational quantum circuits.