SSPS: A Semi-Supervised Pattern Shift for Classification

摘要

Recently, a great amount of efforts have been spent in the research of unsupervised and (semi-)supervised dimensionality reduction (DR) techniques, and DR as a preprocessor is widely applied into classification learning in practice. However, on the one hand, many DR approaches cannot necessarily lead to a better classification performance. On the other hand, DR often suffers from the problem of estimation of retained dimensionality for real-world data. Alternatively, in this paper, we propose a new semi-supervised data preprocessing technique, named semi-supervised pattern shift (SSPS). The advantages of SSPS lie in the fact that not only the estimation of retained dimensionality can be avoided naturally, but a new shifted pattern representation that may be more favorable to classification is obtained as well. As a further extension of SSPS, we develop its fast and out-of-sample versions respectively, both of which are based on a shape-preserved subset selection trick. The final experimental results demonstrate that the proposed SSPS is promising and effective in classification application.