Daydreaming Hopfield Networks and their surprising effectiveness on correlated data.

Journal: Neural networks : the official journal of the International Neural Network Society
Published Date:

Abstract

To improve the storage capacity of the Hopfield model, we develop a version of the dreaming algorithm that perpetually reinforces the patterns to be stored (as in the Hebb rule), and erases the spurious memories (as in dreaming algorithms). For this reason, we called it Daydreaming. Daydreaming is not destructive and it converges asymptotically to stationary retrieval maps. When trained on random uncorrelated examples, the model shows optimal performance in terms of the size of the basins of attraction of stored examples and the quality of reconstruction. We also train the Daydreaming algorithm on correlated data obtained via the random-features model and argue that it spontaneously exploits the correlations thus increasing even further the storage capacity and the size of the basins of attraction. Moreover, the Daydreaming algorithm is also able to stabilize the features hidden in the data. Finally, we test Daydreaming on the MNIST dataset and show that it still works surprisingly well, producing attractors that are close to unseen examples and class prototypes.

Authors

  • Ludovica Serricchio
    Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, Rome, 00185, Italy; Center for Life Nano & Neuro-Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, Rome, 00161, Italy.
  • Dario Bocchi
    Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, Rome, 00185, Italy.
  • Claudio Chilin
    Departamento de Física Teórica, Universidad Complutense, Pl. de las Ciencias 1, Madrid, 28040, Spain.
  • Raffaele Marino
    Physics Department, Università degli Studi di Firenze, Via Sansone 1, Firenze, 50019, Italy.
  • Matteo Negri
    Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, Rome, 00185, Italy; CNR-Nanotec Rome unit, Piazzale Aldo Moro 5, Rome, 00185, Italy. Electronic address: matteo.negri@uniroma1.it.
  • Chiara Cammarota
    Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, Rome, 00185, Italy; INFN Sezione di Roma1, Piazzale Aldo Moro 5, Rome, 00185, Italy.
  • Federico Ricci-Tersenghi
    Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, Rome, 00185, Italy; CNR-Nanotec Rome unit, Piazzale Aldo Moro 5, Rome, 00185, Italy; INFN Sezione di Roma1, Piazzale Aldo Moro 5, Rome, 00185, Italy.