We study the problem of determining the Hamiltonian of a fully connect
ed Ising spin glass of N units from a set of measurements, whose sizes
needs to be O(N-2) bits. The student-teacher scenario, used to study
learning in feed-forward neural networks, is here extended to spin sys
tems with arbitrary couplings. The set of measurements consists of dat
a about the local minima of the rugged energy landscape. We compare si
mulations and analytical approximations for the resulting learning cur
ves obtained by using different algorithms. (C) 1998 Elsevier Science
B.V. All rights reserved.