通过硬币投掷模型检测多变量数据中的局部密度异常,定位信号或异常区域。
Detecting Localized Density Anomalies in Multivariate Data via Coin-Flip Statistics
- 将最近邻序列转为二进制序列,用二项分布检验点的异常性。
- 在真实数据中成功识别出粒子物理和气候数据中的局部异常模式。
- 可生成可解释的异常集合,适合科学发现与背景建模差异分析。
检测两个样本间的局部差异是科学数据分析的核心任务,用于识别信号事件、状态变化或模型偏差。本文提出EagleEye方法,可在多维特征空间中定位局部过密与欠密区域。该方法将每个点的k近邻列表按顺序编码为二进制归属序列,并检验其累积成功次数是否符合二项分布(即硬币投掷)的零假设。当存在真实局部异常时,邻居更倾向于来自某一数据集,导致成功次数显著高于二项分布预期。这些点级检测结果通过确定性优化流程整合为可解释的异常集合,同时可估计不可约背景与局部异常纯度。我们在三个场景中验证了EagleEye的有效性:首先在已知局部过/欠密的人工数据上测试;其次在粒子对撞机实验中用于新物理搜索,应对系统性背景建模差异;最后在气候分析中揭示时空温度模式的局部变化。方法能精准定位异常区域并提供定量解释。
原文摘要 · Abstract (English)
Detecting localized differences between two samples is a central task in scientific data analysis, required for the identification of signal events, regime changes, or model mismatch. We introduce EagleEye, a method that pinpoints local over- and under-densities in multivariate feature spaces. EagleEye assigns each point an anomaly score by encoding its ordered k-nearest-neighbour list as a binary membership sequence and testing whether the cumulative number of successes in this sequence is consistent with a binomial (coin-flipping) null model. In the presence of a genuine local anomaly, neighbours will preferentially belong to one of the two datasts, yielding an excess of ``successes'' relative to the binomial null model. These local, pointwise detections are consolidated into interpretable anomaly sets through a deterministic refinement procedure that can also estimate the irreducible background and local density anomaly purity. We demonstrate EagleEye's efficacy in three scenarios. We first consider an artificial data example with known localized over- and under-densities. Second, we demonstrate how EagleEye may be used for new physics searches at particle collider experiments in the presence of systematic background modelling differences. Finally, we conduct a climate analysis study that reveals localized changes in spatiotemporal temperature-pattern recurrence.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。