Conformal selection (CS) uses calibration data to identify test inputs whose unobserved outcomes are likely to satisfy a pre-specified minimal quality requirement, while controlling the false discovery rate (FDR). Existing methods fix the target FDR level before observing data, which prevents the user from adapting the balance between number of selected test inputs and FDR to downstream needs and constraints based on the available data. For example, in genomics or neuroimaging, researchers often inspect the distribution of test statistics, and decide how aggressively to pursue candidates based on observed evidence strength and available follow-up resources. To address this limitation, we introduce {post-hoc CS} (PH-CS), which generates a path of candidate selection sets, each paired with a data-driven false discovery proportion (FDP) estimate. PH-CS lets the user select any operating point on this path by maximizing a user-specified utility, arbitrarily balancing selection size and FDR. Building on conformal e-variables and the e-Benjamini-Hochberg (e-BH) procedure, PH-CS is proved to provide a finite-sample post-hoc reliability guarantee whereby the ratio between estimated FDP level and true FDP is, on average, upper bounded by $1$, so that the average estimated FDP is, to first order, a valid upper bound on the true FDR. PH-CS is extended to control quality defined in terms of a general risk. Experiments on synthetic and real-world datasets demonstrate that, unlike CS, PH-CS can consistently satisfy user-imposed utility constraints while producing reliable FDP estimates and maintaining competitive FDR control.
翻译:共形选择(CS)利用校准数据识别未观测结果可能满足预设最低质量要求的测试输入,同时控制错误发现率(FDR)。现有方法在观察数据前固定目标FDR水平,这阻碍了用户根据下游需求和可用数据约束来调整所选测试输入数量与FDR之间的平衡。例如,在基因组学或神经影像学中,研究者通常检查检验统计量的分布,并根据观察到的证据强度和可用的后续资源决定是否进行激进地筛选候选者。为解决此局限,我们提出后验共形选择(PH-CS),该方法生成一条候选选择集路径,每个集合均与数据驱动的错误发现比例(FDP)估计值配对。PH-CS允许用户通过最大化自定义效用函数,任意平衡选择规模与FDR,从而选取该路径上的任意工作点。基于共形e变量和e-Benjamini-Hochberg(e-BH)程序,PH-CS被证明能提供有限样本下的后验可靠性保证:估计FDP水平与真实FDP之比平均上界为$1$,使得估计FDP均值在一阶近似下是真实FDR的有效上界。PH-CS还可扩展为控制基于一般风险定义的质量。在合成数据集和真实数据集上的实验表明,与CS不同,PH-CS能持续满足用户施加的效用约束,同时产生可靠的FDP估计并保持有竞争力的FDR控制。