Comparison of regression models.

alinear regression model (linear); double-logistic regression model (dlog); 3rd order monotone splines regression model (splines).
bstandard weighted F test (F); permutation F test (Fperm); a weighted version of a test to compare non-nested regression models (LV) as described in [112].
cshown is the probability that model A (null hypothesis) fits the data better than model B (alternative hypothesis); asterisks (*) highlight significant values to reject the null in favor of the alternative hypothesis using a confidence level of 0.05; probabilities are calculated separately for ORF1a, ORF1b, 3′ORFs as well as the complete model combining the three coding plus the two UTR regions (total).
dnone of the 1 million permutations resulted in an F larger than that of the non-permuted dataset.