arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2402.01635stat.MEcs.LGstat.COstat.ML
收藏

基于自动方差选择的 \ extit{k}-NN 算法的条件均值与方差估计

Conditional Mean and Variance Estimation via \textit{k}-NN Algorithm with Automated Variance Selection

Harvard T.H. Chan School of Public Health(哈佛大学T.H. Chan公共卫生学院);University of Santiago de Compostela(圣西蒙大学);University of California, Los Angeles(加州大学洛杉矶分校)

Marcos Matabuena, Juan C. Vidal, Oscar Hernan Madrid Padilla, Jukka-Pekka Onnela

AI总结:

提出一种结合数据驱动变量选择的k-NN回归方法,联合估计条件均值与方差,实现快速收敛并在模拟和生物医学应用中优于传统k-NN。

摘要:

我们提出了一种新颖的 \ extit{k}-最近邻(\ extit{k}-NN)回归方法,用于联合估计条件均值和方差。所提出的算法保留了经典非参数 \ extit{k}-NN 模型的计算效率和流形学习能力,同时整合了一个数据驱动的变量选择步骤,以提升经验性能。通过准确估计条件均值和方差回归函数,该方法有效地重构了多种尺度与位置生成模型族的条件分布和密度函数。我们证明了我们的估计量能够达到快速收敛速率,并推导出选择平滑参数~$k$ 的实用规则,这些规则在有限样本情形下增强了算法的精度。针对低维、中等维度和高维协变量空间的大量模拟,以及一个真实的生物医学应用,表明所提出的方法能够持续优于传统的 \ extit{k-NN} 回归算法,同时在模型输出上更具可解释性。

英文摘要:

We introduce a novel \textit{k}-nearest neighbor (\textit{k}-NN) regression method for joint estimation of the conditional mean and variance. The proposed algorithm preserves the computational efficiency and manifold-learning capabilities of classical non-parametric \textit{k}-NN models, while integrating a data-driven variable selection step that improves empirical performance. By accurately estimating both conditional mean and variance regression functions, the method effectively reconstructs the conditional distribution and density functions for multiple families of scale-and-localization generative models. We show that our estimator can achieve fast convergence rates, and we derive practical rules for selecting the smoothing parameter~$k$ that enhance the precision of the algorithm in finite sample regimes. Extensive simulations for low, moderate and large-dimensional covariate spaces, together with a real-world biomedical application, demonstrate that the proposed method can consistently outperform the conventional \textit{k-NN} regression algorithm while being more interpretable in the model output.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑