论文标题
加速分布式SGD用于使用迭代预处理进行线性回归
Accelerating Distributed SGD for Linear Regression using Iterative Pre-Conditioning
论文作者
论文摘要
本文考虑了多代理分布式线性最小二乘问题。该系统包括多个代理,每个代理都有一组本地观察到的数据点,以及代理可以与之交互的通用服务器。代理的目标是计算最适合所有代理观察到的集体数据点的线性模型。在基于服务器的分布式设置中,服务器无法访问代理持有的数据点。最近提出的迭代预先调节梯度散发(IPG)方法已显示出比解决此问题的其他现有分布式算法更快的收敛速度。在IPG算法中,服务器和代理执行许多迭代计算。这些迭代中的每一个都取决于代理观察到的整个数据点,以更新解决方案的当前估计值。在这里,我们将迭代预处理的概念扩展到随机设置,在每个迭代时,服务器都会根据单个随机选择的数据点更新估计值和迭代预处理矩阵。我们表明,我们提出的迭代预先调节的随机梯度散发(IPSG)方法在期望与溶液的接近度时线性收敛。重要的是,我们从经验上表明,提出的IPSG方法的收敛率与突出的随机算法相比,用于求解基于服务器的网络中的线性最小二乘问题。
This paper considers the multi-agent distributed linear least-squares problem. The system comprises multiple agents, each agent with a locally observed set of data points, and a common server with whom the agents can interact. The agents' goal is to compute a linear model that best fits the collective data points observed by all the agents. In the server-based distributed settings, the server cannot access the data points held by the agents. The recently proposed Iteratively Pre-conditioned Gradient-descent (IPG) method has been shown to converge faster than other existing distributed algorithms that solve this problem. In the IPG algorithm, the server and the agents perform numerous iterative computations. Each of these iterations relies on the entire batch of data points observed by the agents for updating the current estimate of the solution. Here, we extend the idea of iterative pre-conditioning to the stochastic settings, where the server updates the estimate and the iterative pre-conditioning matrix based on a single randomly selected data point at every iteration. We show that our proposed Iteratively Pre-conditioned Stochastic Gradient-descent (IPSG) method converges linearly in expectation to a proximity of the solution. Importantly, we empirically show that the proposed IPSG method's convergence rate compares favorably to prominent stochastic algorithms for solving the linear least-squares problem in server-based networks.