The Role of Structure and Complexity on Reservoir Computing Quality

  • Matthew DaleEmail author
  • Jack Dewhirst
  • Simon O’Keefe
  • Angelika Sebald
  • Susan Stepney
  • Martin A. Trefzer
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11493)


We explore the effect of structure and connection complexity on the dynamical behaviour of Reservoir Computers (RC). At present, considerable effort is taken to design and hand-craft physical reservoir computers. Both structure and physical complexity are often pivotal to task performance, however, assessing their overall importance is challenging. Using a recently proposed framework, we evaluate and compare the dynamical freedom (referring to quality) of neural network structures, as an analogy for physical systems. The results quantify how structure affects the range of behaviours exhibited by these networks. It highlights that high quality reached by more complex structures is often also achievable in simpler structures with greater network size. Alternatively, quality is often improved in smaller networks by adding greater connection complexity. This work demonstrates the benefits of using abstract behaviour representation, rather than evaluation through benchmark tasks, to assess the quality of computing substrates, as the latter typically has biases, and often provides little insight into the complete computing quality of physical systems.


Reservoir computing Unconventional computing Echo state networks Structure Complexity 



This work is part of the SpInspired project, funded by EPSRC grant EP/R032823/1. Jack Dewhirst is funded by an EPSRC DTP PhD studentship.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Matthew Dale
    • 1
    • 4
    Email author
  • Jack Dewhirst
    • 1
    • 4
  • Simon O’Keefe
    • 1
    • 4
  • Angelika Sebald
    • 2
    • 4
  • Susan Stepney
    • 1
    • 4
  • Martin A. Trefzer
    • 3
    • 4
  1. 1.Department of Computer ScienceUniversity of YorkYorkUK
  2. 2.Department of ChemistryUniversity of YorkYorkUK
  3. 3.Department of Electronic EngineeringUniversity of YorkYorkUK
  4. 4.York Cross-disciplinary Centre for Systems AnalysisYorkUK

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