A Team of Continuous-Action Learning Automata for Noise-Tolerant Learning of Half-Spaces

作者：Sastry P S^*; Nagendra G D; Manwani Naresh

来源：IEEE Transactions on Systems, Man, and Cybernetics - Part B: Cybernetics , 2010, 40(1): 19-28.

DOI：10.1109/TSMCB.2009.2032155

• Continuous-action-set learning automata (CALA)
• hyperplane classifiers
• learning automata
• noise-tolerant learning
• stochastic optimization
• team of automata

Learning automata are adaptive decision making devices that are found useful in a variety of machine learning and pattern recognition applications. Although most learning automata methods deal with the case of finitely many actions for the automaton, there are also models of continuous-action-set learning automata (CALA). A team of such CALA can be useful in stochastic optimization problems where one has access only to noise-corrupted values of the objective function. In this paper, we present a novel formulation for noise-tolerant learning of linear classifiers using a CALA team. We consider the general case of nonuniform noise, where the probability that the class label of an example is wrong may be a function of the feature vector of the example. The objective is to learn the underlying separating hyperplane given only such noisy examples. We present an algorithm employing a team of CALA and prove, under some conditions on the class conditional densities, that the algorithm achieves noise-tolerant learning as long as the probability of wrong label for any example is less than 0.5. We also present some empirical results to illustrate the effectiveness of the algorithm.

• 出版日期2010-2