Title
F-Measure Optimization for Multi-class, Imbalanced Emotion Classification Tasks
Abstract
Recent NLP breakthroughs have significantly advanced the state of emotion classification (EC) over text data. However, current treatments guide learning by traditional performance metrics, such as classification error rate, which are not suitable for the highly-imbalanced EC problems; in fact, EC models are predominantly evaluated by variations of the F-measure, recognizing the data imbalance. This paper addresses the dissonance between the learning objective and the performance evaluation for EC with moderate to severe data imbalance. We propose a series of increasingly powerful algorithms for F-measure improvement. An ablation study demonstrates the superiority of learning an optimal class decision threshold. Increased performance is demonstrated when joint learning is carried out over both the representation and the class decision thresholds. Thorough empirical evaluation on benchmark EC datasets that span the spectrum of number of classes and class imbalance shows clear F-measure improvements over baseline models, with good improvements over pre-trained deep models and higher improvements over untrained deep architectures.
Year
DOI
Venue
2022
10.1007/978-3-031-15919-0_14
ARTIFICIAL NEURAL NETWORKS AND MACHINE LEARNING - ICANN 2022, PT I
Keywords
DocType
Volume
Emotion classification, Multi-class classification, Class imbalance, F-measure optimization, Transformer models, Deep learning
Conference
13529
ISSN
Citations 
PageRank 
0302-9743
0
0.34
References 
Authors
0
3
Name
Order
Citations
PageRank
Toki Tahmid Inan100.68
Mingrui Liu200.68
Amarda Shehu329755.09