Knowledge Extraction from Transducer Neural Networks

Previously neural networks have shown interesting performance results for tasks such as classification, but they still suffer from an insufficient focus on the structure of the knowledge represented therein. In this paper, we analyze various knowledge extraction techniques in detail and we develop new transducer extraction techniques for the interpretation of recurrent neural network learning. First, we provide an overview of different possibilities to express structured knowledge using neural networks. Then, we analyze a type of recurrent network rigorously, applying a broad range of different techniques. We argue that analysis techniques, such as weight analysis using Hinton diagrams, hierarchical cluster analysis, and principal component analysis may be useful for providing certain views on the underlying knowledge. However, we demonstrate that these techniques are too static and too low-level for interpreting recurrent network classifications. The contribution of this paper is a particularly broad analysis of knowledge extraction techniques. Furthermore, we propose dynamic learning analysis and transducer extraction as two new dynamic interpretation techniques. Dynamic learning analysis provides a better understanding of how the network learns, while transducer extraction provides a better understanding of what the network represents.

@Article{Wer00b, 
 	 author =  {Wermter, Stefan},  
 	 title = {Knowledge Extraction from Transducer Neural Networks}, 
 	 journal = {Journal of Applied Intelligence},
 	 number = {1--2},
 	 volume = {12},
 	 pages = {27--42},
 	 year = {2000},
 	 month = {Feb},
 	 publisher = {Springer},
 	 doi = {10.1023/A:1008320219610}, 
 }