Interpretable Models Capable of Handling Systematic Missingness in Imbalanced Classes and Heterogeneous Datasets

TL;DR

This paper introduces a family of interpretable prototype-based models designed to effectively handle systematic missingness, class imbalance, and heterogeneity in medical datasets, achieving competitive or superior performance while maintaining transparency.

Contribution

The paper presents novel prototype-based interpretable models that address common issues in medical data, and a strategy to combine ensemble benefits with model interpretability.

Findings

Models perform comparably or better than alternatives.

Models are transparent and computationally inexpensive.

Effective on real-world and synthetic datasets.

Abstract

Application of interpretable machine learning techniques on medical datasets facilitate early and fast diagnoses, along with getting deeper insight into the data. Furthermore, the transparency of these models increase trust among application domain experts. Medical datasets face common issues such as heterogeneous measurements, imbalanced classes with limited sample size, and missing data, which hinder the straightforward application of machine learning techniques. In this paper we present a family of prototype-based (PB) interpretable models which are capable of handling these issues. The models introduced in this contribution show comparable or superior performance to alternative techniques applicable in such situations. However, unlike ensemble based models, which have to compromise on easy interpretation, the PB models here do not. Moreover we propose a strategy of harnessing the power of ensembles while maintaining the intrinsic interpretability of the PB models, by averaging the model parameter manifolds. All the models were evaluated on a synthetic (publicly available dataset) in addition to detailed analyses of two real-world medical datasets (one publicly available). Results indicated that the models and strategies we introduced addressed the challenges of real-world medical data, while remaining computationally inexpensive and transparent, as well as similar or superior in performance compared to their alternatives.