Numerical tests of overfitting in the independent model. Each row
corresponds to an independent model fit to a “training” MSA
data-set with different MSA depth N, generated from a reference
independent model with L = 1000, q = 16, and
A pseudocount of 1/N is used
to avoid issues with unsampled residues. The green distribution shows estimated
energies of “random” sequences with equal residue probabilities,
the blue distribution shows energies of the training MSA, and the red
distribution are energies of a “test” MSA independently generated
from the reference model. The black arrow on the x axis marks the expected
energy of the training MSA based on the mean energy of the test MSA minus the
shift δE computed using Eqs. 5 and 7, showing good agreement. The models are evaluated in the zero-mean
gauge.