Using Hybrid Hadamard Error Correcting Output Codes for Multi-class Problem Based on Support Vector Machines

The error-correcting output codes (ECOC) method reduces the multi-class learning problem into a series of binary classifiers. In this paper, we propose a modified Hadamard-type ECOC method. This method uses both N´th order and N/2´th-order Hadamard matrix to construct error correcting output codes, which is called hybrid Hadamard ECOC. Experiments based on dichotomizers of support vector machines (SVM) have been carried out to evaluate the performance of the proposed method. When compared to normal Hadamard ECOC, computation of the method is reduced greatly while the accuracy of classification only drops slightly