Auditing Facial Emotion Recognition Datasets for Posed Expressions and Racial Bias

TL;DR

This paper audits facial emotion recognition datasets for posed expressions and racial bias, revealing significant posed images and racial disparities that affect model performance and fairness in real-world applications.

Contribution

It introduces a methodology to identify posed images in FER datasets and highlights racial biases affecting model predictions and fairness.

Findings

Many images labeled as in-the-wild were actually posed.

FER models perform worse on spontaneous expressions.

Models tend to misclassify darker-skinned individuals' emotions.

Abstract

Facial expression recognition (FER) algorithms classify facial expressions into emotions such as happy, sad, or angry. An evaluative challenge facing FER algorithms is the fall in performance when detecting spontaneous expressions compared to posed expressions. An ethical (and evaluative) challenge facing FER algorithms is that they tend to perform poorly for people of some races and skin colors. These challenges are linked to the data collection practices employed in the creation of FER datasets. In this study, we audit two state-of-the-art FER datasets. We take random samples from each dataset and examine whether images are spontaneous or posed. In doing so, we propose a methodology for identifying spontaneous or posed images. We discover a significant number of images that were posed in the datasets purporting to consist of in-the-wild images. Since performance of FER models vary between spontaneous and posed images, the performance of models trained on these datasets will not represent the true performance if such models were to be deployed in in-the-wild applications. We also observe the skin color of individuals in the samples, and test three models trained on each of the datasets to predict facial expressions of people from various races and skin tones. We find that the FER models audited were more likely to predict people labeled as not white or determined to have dark skin as showing a negative emotion such as anger or sadness even when they were smiling. This bias makes such models prone to perpetuate harm in real life applications.