论文标题
稀疏多任务回归的选择性推断,并在神经影像中应用
Selective Inference for Sparse Multitask Regression with Applications in Neuroimaging
论文作者
论文摘要
多任务学习经常用于对一组相同特征的一组相关响应变量进行建模,从而相对于分别处理每个响应变量的方法提高了预测性能和建模精度。尽管多任务学习的潜力比单任务替代方案具有更强大的推理,但该领域的先前工作在很大程度上忽略了不确定性量化。我们在本文中的重点是神经影像学中常见的多任务问题,其目标是了解多个认知任务分数(或其他主题级评估)与从成像收集的大脑连接数据之间的关系。我们提出了一个选择性推断以解决此问题的框架,并具有以下灵活性:(i)通过稀疏性惩罚共同确定每个任务的相关协变量,(ii)基于估计的稀疏结构在模型中进行有效推理。我们的框架为推理提供了新的有条件过程,基于对选择事件的改进,该事件产生了可拖延的选择调整后的可能性。这提供了一个近似的估计方程式系统的最大似然推理,可通过单个凸优化问题求解,并使我们能够在大约正确的覆盖范围内有效地形成置信区间。我们的选择推理方法应用于青少年脑认知发展(ABCD)研究(ABCD)研究的模拟数据和数据,与常用的替代方案(例如数据分裂)相比,我们的选择性推理方法产生的推理方法更紧密。我们还通过模拟证明,与单任务方法相比,使用选择性推理的多任务学习可以更准确地恢复真实的信号。
Multi-task learning is frequently used to model a set of related response variables from the same set of features, improving predictive performance and modeling accuracy relative to methods that handle each response variable separately. Despite the potential of multi-task learning to yield more powerful inference than single-task alternatives, prior work in this area has largely omitted uncertainty quantification. Our focus in this paper is a common multi-task problem in neuroimaging, where the goal is to understand the relationship between multiple cognitive task scores (or other subject-level assessments) and brain connectome data collected from imaging. We propose a framework for selective inference to address this problem, with the flexibility to: (i) jointly identify the relevant covariates for each task through a sparsity-inducing penalty, and (ii) conduct valid inference in a model based on the estimated sparsity structure. Our framework offers a new conditional procedure for inference, based on a refinement of the selection event that yields a tractable selection-adjusted likelihood. This gives an approximate system of estimating equations for maximum likelihood inference, solvable via a single convex optimization problem, and enables us to efficiently form confidence intervals with approximately the correct coverage. Applied to both simulated data and data from the Adolescent Brain Cognitive Development (ABCD) study, our selective inference methods yield tighter confidence intervals than commonly used alternatives, such as data splitting. We also demonstrate through simulations that multi-task learning with selective inference can more accurately recover true signals than single-task methods.