One-Class Classification Using Quasi-Linear Support Vector Machine

This paper proposes a novel method for one-class classification by using support vector machine (SVM) based on a divide-and-conquer strategy. An s% winner-take-all autoencoder is applied to realize a sophisticated partitioning which divides the dataset into many clusters. For each cluster, data points are separated from the origin in the feature space like a traditional one-class SVM (OCSVM). By designing a gated linear network, and generating the gate signal from the autoencoder, the proposed OCSVM is implemented in an exact same way as a standard OCSVM with a quasi-linear kernel composed by using a base kernel with the gate signals. Comparing to a traditional OCSVM, the proposed quasi-linear OCSVM is expected to capture a more compact region in the input space. The compact region will decrease the probability of outlier objects falling inside the domain of classifier, which give a better performance. The proposed quasi-linear OCSVM method is applied to different real-world datasets, and simulation results confirm the effectiveness of the proposed method.