Domain Transfer Multi-Instance Dictionary Learning

TL;DR

This paper introduces a novel domain transfer learning approach for multi-instance data, adapting a source domain dictionary and classifier to the target domain through an iterative optimization process.

Contribution

It proposes a method to adapt pre-trained multi-instance dictionaries and classifiers to new domains using an adaptive linear function and joint optimization.

Findings

Outperforms existing domain transfer multi-instance learning methods

Demonstrates effectiveness on several benchmark datasets

Shows improved classification accuracy in target domains

Abstract

In this paper, we invest the domain transfer learning problem with multi-instance data. We assume we already have a well-trained multi-instance dictionary and its corresponding classifier from the source domain, which can be used to represent and classify the bags. But it cannot be directly used to the target domain. Thus we propose to adapt them to the target domain by adding an adaptive term to the source domain classifier. The adaptive function is a linear function based a domain transfer multi-instance dictionary. Given a target domain bag, we first map it to a bag-level feature space using the domain transfer dictionary, and then apply a the linear adaptive function to its bag-level feature vector. To learn the domain-transfer dictionary and the adaptive function parameter, we simultaneously minimize the average classification error of the target domain classifier over the target domain training set, and the complexities of both the adaptive function parameter and the domain transfer dictionary. The minimization problem is solved by an iterative algorithm which update the dictionary and the function parameter alternately. Experiments over several benchmark data sets show the advantage of the proposed method over existing state-of-the-art domain transfer multi-instance learning methods.