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arXiv · 1901.05335

A review of domain adaptation without target labels

Wouter M. Kouw·Marco Loog
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Abstract

Domain adaptation has become a prominent problem setting in machine learning and related fields. This review asks the question: how can a classifier learn from a source domain and generalize to a target domain? We present a categorization of approaches, divided into, what we refer to as, sample-based, feature-based and inference-based methods. Sample-based methods focus on weighting individual observations during training based on their importance to the target domain. Feature-based methods revolve around on mapping, projecting and representing features such that a source classifier performs well on the target domain and inference-based methods incorporate adaptation into the parameter estimation procedure, for instance through constraints on the optimization procedure. Additionally, we review a number of conditions that allow for formulating bounds on the cross-domain generalization error. Our categorization highlights recurring ideas and raises questions important to further research.

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Wouter M. Kouw, Marco Loog. 2019-01-16. A review of domain adaptation without target labels. https://doi.org/10.1109/tpami.2019.2945942

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