Akaike's An Information Criterion for gips class
Arguments
- object
An object of class
gips. Usually, a result of afind_MAP().- ...
Further arguments will be ignored.
- k
Numeric, the penalty per parameter to be used. The default
k = 2is the classical AIC.
Value
AIC.gips() returns calculated Akaike's An Information Criterion
When the multivariate normal model does not exist
(number_of_observations < n0), it returns NULL.
When the multivariate normal model cannot be reasonably approximated
(output of project_matrix() is singular), it returns Inf.
In both failure situations, shows a warning.
More information can be found in the Existence of likelihood
section of logLik.gips().
BIC.gips() returns calculated
Schwarz's Bayesian Information Criterion.
Calculation details
For more details and used formulas, see
the Information Criterion - AIC and BIC section in
vignette("Theory", package = "gips") or its
pkgdown page.
See also
AIC(),BIC()- Generic functions thisAIC.gips()andBIC.gips()extend.find_MAP()- Usually, theAIC.gips()andBIC.gips()are called on the output offind_MAP().logLik.gips()- Calculates the log-likelihood for thegipsobject. An important part of the Information Criteria.
Examples
S <- matrix(c(
5.15, 2.05, 3.10, 1.99,
2.05, 5.09, 2.03, 3.07,
3.10, 2.03, 5.21, 1.97,
1.99, 3.07, 1.97, 5.13
), nrow = 4)
g <- gips(S, 14)
g_map <- find_MAP(g, optimizer = "brute_force")
#> ================================================================================
AIC(g) # 238
#> [1] 237.6098
AIC(g_map) # 224 < 238, so g_map is better than g according to AIC
#> [1] 223.6188
# ================================================================================
BIC(g) # 244
#> [1] 244.0004
BIC(g_map) # 226 < 244, so g_map is better than g according to BIC
#> [1] 225.536