Multi-Sample $\zeta$-mixup: Richer, More Realistic Synthetic Samples from a $p$-Series Interpolant

TL;DR

This paper introduces $ta$-mixup, a new data augmentation method that generalizes mixup by combining multiple samples using a $p$-series interpolant, resulting in more realistic, diverse, and intrinsic data representations for improved model training.

Contribution

The paper proposes $ta$-mixup, a novel extension of mixup that combines multiple samples with a $p$-series interpolant, enhancing data realism and preserving dataset dimensionality.

Findings

$ta$-mixup produces more realistic synthetic samples.

It better preserves the intrinsic dimensionality of data.

It outperforms mixup and traditional augmentation on various datasets.

Abstract

Modern deep learning training procedures rely on model regularization techniques such as data augmentation methods, which generate training samples that increase the diversity of data and richness of label information. A popular recent method, mixup, uses convex combinations of pairs of original samples to generate new samples. However, as we show in our experiments, mixup can produce undesirable synthetic samples, where the data is sampled off the manifold and can contain incorrect labels. We propose $\zeta$-mixup, a generalization of mixup with provably and demonstrably desirable properties that allows convex combinations of $N \geq 2$ samples, leading to more realistic and diverse outputs that incorporate information from $N$ original samples by using a $p$-series interpolant. We show that, compared to mixup, $\zeta$-mixup better preserves the intrinsic dimensionality of the original datasets, which is a desirable property for training generalizable models. Furthermore, we show that our implementation of $\zeta$-mixup is faster than mixup, and extensive evaluation on controlled synthetic and 24 real-world natural and medical image classification datasets shows that $\zeta$-mixup outperforms mixup and traditional data augmentation techniques.