手法を比較

	エコー状態ネットワーク	標本エントロピー
分野	深層学習	複雑系
系統	Machine learning	Machine learning
提唱年	2004	2000
提唱者	Herbert Jaeger & Harald Haas	Richman & Moorman
種類	Recurrent neural network with fixed random reservoir	Nonlinear entropy measure
原典	Jaeger, H., & Haas, H. (2004). Harnessing nonlinearity: Predicting chaotic systems and saving energy in wireless communication. Science, 304(5667), 78–80.	Richman, J. S., & Moorman, J. R. (2000). Physiological time-series analysis using approximate entropy and sample entropy. American Journal of Physiology, 278(6), H2039–H2049.
別名	ESN, Liquid State Machine (related formulation), Reservoir Computing, Yankı Durum Ağı	SampEn, Sample Entropy (SampEn), Örneklem Entropisi, Nonlinear Complexity Measure
関連	3	2
概要	An Echo State Network (ESN) is a type of recurrent neural network introduced by Herbert Jaeger and Harald Haas in 2004 that exploits a large, randomly connected, fixed recurrent layer — the reservoir — to project input signals into a high-dimensional nonlinear space. Only the linear output weights are trained, typically via ridge regression, making ESNs computationally inexpensive yet highly expressive for temporal and chaotic time-series modeling tasks.	Sample Entropy (SampEn) is a nonlinear measure of the complexity and regularity of a time series. Introduced by Richman and Moorman in 2000 as an improvement over Approximate Entropy (ApEn), it quantifies the likelihood that similar patterns of a given length in the series remain similar when extended by one additional data point. A higher SampEn value indicates greater irregularity and complexity, while a lower value indicates more regularity or self-similarity.