Validation of the training set for developing the four-body statistical potentials

A random subset that is 70% of the size of the original training set (which had 1167 chains) is selected. The four-body potentials are developed using this subset alone. This experiment is repeated ten times. The following table gives the correlation between the log-likelihoods thus developed (using a 70% subset) and the original four-body potentials (developed using the full training set). Each of the subsets provided scores that are highly correlated (0.88) with the original potentials.

SET	correlation
70_set1	0.88
70_set2	0.88
70_set3	0.88
70_set4	0.88
70_set5	0.88
70_set6	0.87
70_set7	0.89
70_set8	0.87
70_set9	0.88
70_set10	0.89

The correlation coefficients given above are calculated for the whole 8855 x 5 table of log-likelihoods (8855 possible quadruplet compositions in

each of the five classes defined based on backbone chain connectivity). On the other, if only those log-likelihoods were involved in the calculation for which quadruplets were observed in both the 70% subset as well as in the whole training set, much higher correlation coefficients are obtained.