Adaptive fusion and co-operative training for classifier ensembles

In this paper, architectures and methods of decision aggregation in classifier ensembles are investigated. Typically, ensembles are designed in such a way that each classifier is trained independently and the decision fusion is performed as a post-process module. In this study, however, we are interested in making the fusion a more adaptive process. We first propose a new architecture that utilizes the features of a problem to guide the decision fusion process. By using both the features and classifiers outputs, the recognition strengths and weaknesses of the different classifiers are identified. This information is used to improve overall generalization capability of the system. Furthermore, we propose a co-operative training algorithm that allows the final classification to determine whether further training should be carried out on the components of the architecture. The performance of the proposed architecture is assessed by testing it on several benchmark problems. The new architecture shows improvement over existing aggregation techniques. Moreover, the proposed co-operative training algorithm provides a means to limit the users' intervention, and maintains a level of accuracy that is competitive to that of most other approaches.

[1]  Belur V. Dasarathy,et al.  Decision fusion , 1994 .

[2]  Mohamed S. Kamel,et al.  Data Dependence in Combining Classifiers , 2003, Multiple Classifier Systems.

[3]  Fakhri Karray,et al.  Feature-based decision aggregation in modular neural network classifiers , 1999, Pattern Recognit. Lett..

[4]  Mohamed S. Kamel,et al.  Modular Neural Network Classifiers: A Comparative Study , 1998, J. Intell. Robotic Syst..

[5]  Josef Kittler,et al.  Combining multiple classifiers by averaging or by multiplying? , 2000, Pattern Recognit..

[6]  B. Ripley,et al.  Pattern Recognition , 1968, Nature.

[7]  David H. Wolpert,et al.  Stacked generalization , 1992, Neural Networks.

[8]  Amanda J. C. Sharkey,et al.  Combining Artificial Neural Nets: Ensemble and Modular Multi-Net Systems , 1999 .

[9]  Ludmila I. Kuncheva Diversity in multiple classifier systems , 2005, Inf. Fusion.

[10]  Jiri Matas,et al.  On Combining Classifiers , 1998, IEEE Trans. Pattern Anal. Mach. Intell..

[11]  Luís A. Alexandre,et al.  On combining classifiers using sum and product rules , 2001, Pattern Recognit. Lett..

[12]  Carmen García-Mateo,et al.  On combining classifiers for speaker authentication , 2003, Pattern Recognit..

[13]  Amanda J. C. Sharkey,et al.  Multi-Net Systems , 1999 .

[14]  Subhash C. Bagui,et al.  Combining Pattern Classifiers: Methods and Algorithms , 2005, Technometrics.

[15]  James C. Bezdek,et al.  Decision templates for multiple classifier fusion: an experimental comparison , 2001, Pattern Recognit..

[16]  Armando Freitas da Rocha,et al.  Neural Nets , 1992, Lecture Notes in Computer Science.

[17]  D. Signorini,et al.  Neural networks , 1995, The Lancet.

[18]  Robert A. Jacobs,et al.  Hierarchical Mixtures of Experts and the EM Algorithm , 1993, Neural Computation.

[19]  Naonori Ueda,et al.  Optimal Linear Combination of Neural Networks for Improving Classification Performance , 2000, IEEE Trans. Pattern Anal. Mach. Intell..

[20]  Luc Vandendorpe,et al.  Multiple classifier combination for face-based identity verification , 2004, Pattern Recognit..

[21]  Joydeep Ghosh,et al.  Hierarchical Fusion of Multiple Classifiers for Hyperspectral Data Analysis , 2002, Pattern Analysis & Applications.

[22]  Misha Pavel,et al.  Robust image recognition by fusion of contextual information , 2002, Inf. Fusion.

[23]  Yoav Freund,et al.  Experiments with a New Boosting Algorithm , 1996, ICML.

[24]  Catherine Blake,et al.  UCI Repository of machine learning databases , 1998 .

[25]  Ching Y. Suen,et al.  The Combination of Multiple Classifiers by A Neural Network Approach , 1995, Int. J. Pattern Recognit. Artif. Intell..

[26]  Robert P. W. Duin,et al.  The combining classifier: to train or not to train? , 2002, Object recognition supported by user interaction for service robots.

[27]  Kevin W. Bowyer,et al.  Combination of multiple classifiers using local accuracy estimates , 1996, Proceedings CVPR IEEE Computer Society Conference on Computer Vision and Pattern Recognition.

[28]  Andreas Stafylopatis,et al.  A divide-and-conquer method for multi-net classifiers , 2003, Pattern Analysis & Applications.

[29]  G. G. Stokes "J." , 1890, The New Yale Book of Quotations.

[30]  Mohamed S. Kamel,et al.  Decision fusion in neural network ensembles , 2001, IJCNN'01. International Joint Conference on Neural Networks. Proceedings (Cat. No.01CH37222).

[31]  Ludmila I. Kuncheva,et al.  Combining Pattern Classifiers: Methods and Algorithms , 2004 .