Title: A Unimodal, Uncertainty-Aware Deep Learning Approach for Ordinal Regression. Abstract: Ordinal regression is an important area in machine learning, and many algorithms were proposed to approach it. In this work, we propose an ordinal regression prediction algorithm, based on deep learning machinery and inspired by the well-known Proportional Odds model. Our proposed approach has three key components: first, it is designed to guarantee unimodal output probabilities, which is a desired element in many real world applications. Second, we argue that the standard maximum likelihood is sub-optimal for ordinal regression problems and train our model using optimal transport loss, as it naturally captures the order of the classes. Third, we design a novel regularizer aiming to make the model uncertainty-aware, in the sense of making the model more confident about correct predictions, comparing to wrong predictions. In addition, we propose a novel uncertainty-awareness evaluation measure. Experimental results on eight real-world datasets
demonstrate that our proposed approach consistently performs on par with and often better than several recently proposed deep learning approaches for ordinal regression, in terms of both accuracy and uncertainty-awareness, while having a guarantee on the output unimodality.