INDperform (version 0.2.2)

select_model: Select the best correlation structure in the GAMM

Description

The function selects and returns the best GAMM out of the six GAMMs computed in model_gamm. In the case that the GAMM without any correlation structure performs best, the output tibble contains the information from the original model_gam output tibble (therefore needed as input).

Usage

select_model(gam_tbl, gamm_tbl)

Arguments

gam_tbl

Output tibble from the model_gam function.

gamm_tbl

Output tibble from the model_gamm function.

Value

select_model returns the same model output tibble as model_gamm but with only one final GAMM for each filtered IND~pressure pair.

Details

The best error structure is chosen here based on the Akaike`s Information Criterion (AIC). The GAMM with the lowest AIC value is selected, but only if the AIC difference to the GAMMs with a less complex error structure is greater than 2 (or respectively 4 or 6 depending on the level of nested complexity) (Burnham and Anderson, 2002). Otherwise the less complex GAMM is chosen. The following hierarchy of complexity is considered:

• no structure < AR1 < AR2 and ARMA1,1 < ARMA2,1 and ARMA1,2

References

Burnham, K.P., Anderson, D.R. (2002) Model Selection and Multimodel Inference - A Practical Information-Theoretic Approach. Springer, New York.

See Also

Other IND~pressure modeling functions: find_id(), ind_init(), model_gamm(), model_gam(), plot_diagnostics(), plot_model(), scoring(), test_interaction()

Examples

# NOT RUN {
# Using some models of the Baltic Sea demo data
test_ids <- c(67:70)
gam_tbl <- model_gam_ex[model_gam_ex$id %in% test_ids,]
gamm_tbl <- model_gamm(ind_init_ex[test_ids,], filter = gam_tbl$tac)
best_gamm <- select_model(gam_tbl, gamm_tbl)
# }