Quantifying Statistical Significance of Neural Network-based Image Segmentation by Selective Inference

TL;DR

This paper introduces a statistical framework using selective inference to quantify the reliability of neural network-based image segmentation, providing valid p-values and controlling false positives in both synthetic and real-world datasets.

Contribution

It develops a novel selective inference algorithm based on the homotopy method for DNN-driven hypotheses, enabling exact p-value computation for segmentation results.

Findings

Successfully controls false positive rate in experiments

Demonstrates computational efficiency of the method

Provides reliable significance assessment in medical imaging

Abstract

Although a vast body of literature relates to image segmentation methods that use deep neural networks (DNNs), less attention has been paid to assessing the statistical reliability of segmentation results. In this study, we interpret the segmentation results as hypotheses driven by DNN (called DNN-driven hypotheses) and propose a method by which to quantify the reliability of these hypotheses within a statistical hypothesis testing framework. Specifically, we consider a statistical hypothesis test for the difference between the object and background regions. This problem is challenging, as the difference would be falsely large because of the adaptation of the DNN to the data. To overcome this difficulty, we introduce a conditional selective inference (SI) framework -- a new statistical inference framework for data-driven hypotheses that has recently received considerable attention -- to compute exact (non-asymptotic) valid p-values for the segmentation results. To use the conditional SI framework for DNN-based segmentation, we develop a new SI algorithm based on the homotopy method, which enables us to derive the exact (non-asymptotic) sampling distribution of DNN-driven hypothesis. We conduct experiments on both synthetic and real-world datasets, through which we offer evidence that our proposed method can successfully control the false positive rate, has good performance in terms of computational efficiency, and provides good results when applied to medical image data.