Cost-Sensitive Reference Pair Encoding for Multi-Label Learning

We propose a novel cost-sensitive multi-label classification algorithm called cost-sensitive random pair encoding (CSRPE). CSRPE reduces the costsensitive multi-label classification problem to many cost-sensitive binary classification problems through the label powerset approach followed by the classic oneversus-one decomposition. While such a näıve reduction results in exponentiallymany classifiers, we resolve the training challenge of building the many classifiers by random sampling, and the prediction challenge of voting from the many classifiers by nearest-neighbor decoding through casting the one-versus-one decomposition as a special case of error-correcting code. Extensive experimental results demonstrate that CSRPE achieves stable convergence and reaches better performance than other ensemble-learning and error-correcting-coding algorithms for multi-label classification. The results also justify that CSRPE is competitive with state-of-the-art cost-sensitive multi-label classification algorithms for cost-sensitive multi-label classification.