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. 2020 Sep 23;8(5):nwaa244. doi: 10.1093/nsr/nwaa244

Table 1.

Evaluations of model performance based on the parsimony tests and repeated k-fold cross validations (10 folds and 10 repeats) in case of optimum u and v and Radius = 20 m.

Radius Species Response Model u v Para Samples R2 logLik AIC BIC RMSE MAE
20 m Beech Survival SIZE 4 38 798 0.011 −1433 2874 2908 0.078 0.012
SIZE + DI 0.2 0 6 38 798 0.028 −1409 2830 2881 0.078 0.012
SIZE + DI + HOI 0.5 0.8 10 38 798 0.062 1360 2739 2825 0.078 0.012
Growth SIZE 2 28 845 0.180 −35 775 71 557 71 582 0.836 0.671
SIZE + DI 1.3 0.8 4 28 845 0.244 −34 611 69 231 69 272 0.803 0.641
SIZE + DI + HOI 1 0.8 8 28 845 0.252 34 443 68 904 68 978 0.799 0.637
Spruce Survival SIZE 4 1058 0.099 −239 486 506 0.244 0.121
SIZE + DI 1 0.5 6 1058 0.219 −207 427 457 0.234 0.111
SIZE + DI + HOI 0.5 0.2 10 1058 0.276 192 405 454 0.233 0.108
Growth SIZE 2 692 0.181 −967 1941 1954 0.978 0.788
SIZE + DI 0.9 1 4 692 0.345 −890 1790 1813 0.878 0.692
SIZE + DI + HOI 1 0.9 8 692 0.361 881 1781 1821 0.873 0.689

Optimum u and v were selected for models with the highest R-squared and likelihood (Table S1). For the parsimony tests, AIC and BIC that were two or more points less than the next best model were considered as a meaningful improvement in in-sample performance. Models with lower RMSE and MAE computed from cross validations had better out-of-sample performance. The numbers in bold indicate that HOI-inclusive models had best performance based on AIC, BIC, RMSE or MAE. Results for the Radius = 10 m and 30 m are presented in Tables S2 and S3.