稀疏决策树优化是AI自成立以来的最基本问题之一,并且是可解释机器学习核心的挑战。稀疏的决策树优化是计算地的艰难,尽管自1960年代以来稳定的努力,但在过去几年中才突破问题,主要是在找到最佳稀疏决策树的问题上。然而,目前最先进的算法通常需要不切实际的计算时间和内存,以找到一些真实世界数据集的最佳或近最优树,特别是那些具有多个连续值的那些。鉴于这些决策树优化问题的搜索空间是大规模的,我们可以实际上希望找到一个稀疏的决策树,用黑盒机学习模型的准确性竞争吗?我们通过智能猜测策略来解决这个问题,可以应用于基于任何最优分支和绑定的决策树算法。我们表明,通过使用这些猜测,我们可以通过多个数量级来减少运行时间,同时提供所得树木可以偏离黑匣子的准确性和表现力的界限。我们的方法可以猜测如何在最佳决策树错误的持续功能,树的大小和下限上进行换算。我们的实验表明,在许多情况下,我们可以迅速构建符合黑匣子型号精度的稀疏决策树。总结:当您在优化时遇到困难时,就猜测。
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Fingerprints are key tools in climate change detection and attribution (D&A) that are used to determine whether changes in observations are different from internal climate variability (detection), and whether observed changes can be assigned to specific external drivers (attribution). We propose a direct D&A approach based on supervised learning to extract fingerprints that lead to robust predictions under relevant interventions on exogenous variables, i.e., climate drivers other than the target. We employ anchor regression, a distributionally-robust statistical learning method inspired by causal inference that extrapolates well to perturbed data under the interventions considered. The residuals from the prediction achieve either uncorrelatedness or mean independence with the exogenous variables, thus guaranteeing robustness. We define D&A as a unified hypothesis testing framework that relies on the same statistical model but uses different targets and test statistics. In the experiments, we first show that the CO2 forcing can be robustly predicted from temperature spatial patterns under strong interventions on the solar forcing. Second, we illustrate attribution to the greenhouse gases and aerosols while protecting against interventions on the aerosols and CO2 forcing, respectively. Our study shows that incorporating robustness constraints against relevant interventions may significantly benefit detection and attribution of climate change.
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