Conformal prediction is a statistical framework that generates prediction
sets containing ground-truth labels with a desired coverage guarantee. The
predicted probabilities produced by machine learning models are generally
miscalibrated, leading to large prediction sets in conformal prediction. In
this paper, we empirically and theoretically show that disregarding the
probabilities' value will mitigate the undesirable effect of miscalibrated
probability values. Then, we propose a novel algorithm named $\textit{Sorted
Adaptive prediction sets}$ (SAPS), which discards all the probability values
except for the maximum softmax probability. The key idea behind SAPS is to
minimize the dependence of the non-conformity score on the probability values
while retaining the uncertainty information. In this manner, SAPS can produce
sets of small size and communicate instance-wise uncertainty. Theoretically, we
provide a finite-sample coverage guarantee of SAPS and show that the expected
value of set size from SAPS is always smaller than APS. Extensive experiments
validate that SAPS not only lessens the prediction sets but also broadly
enhances the conditional coverage rate and adaptation of prediction sets.

通过理论和实验，本文证明了无视概率值可以减轻在 conformal prediction 中概率值失配所导致的大预测集的不良影响。然后，提出了一种名为 “Sorted Adaptive prediction sets” (SAPS) 的新算法，其丢弃除最大 softmax 概率以外的所有概率值，以最小化非符合度分数对概率值的依赖，同时保留不确定性信息，从而生成小型集合并传达逐个实例的不确定性。在理论上，提供了 SAPS 的有限样本覆盖保证，并证明了 SAPS 的预期集合大小始终小于 APS。广泛的实验验证了 SAPS 不仅减小了预测集，还显著提高了预测集的条件覆盖率和适应性。