check_zeroinflation()
checks whether count models are
over- or underfitting zeros in the outcome.
Arguments
- x
Fitted model of class
merMod
,glmmTMB
,glm
, orglm.nb
(package MASS).- tolerance
The tolerance for the ratio of observed and predicted zeros to considered as over- or underfitting zeros. A ratio between 1 +/-
tolerance
is considered as OK, while a ratio beyond or below this threshold would indicate over- or underfitting.
Value
A list with information about the amount of predicted and observed zeros in the outcome, as well as the ratio between these two values.
Details
If the amount of observed zeros is larger than the amount of predicted zeros, the model is underfitting zeros, which indicates a zero-inflation in the data. In such cases, it is recommended to use negative binomial or zero-inflated models.
See also
Other functions to check model assumptions and and assess model quality:
check_autocorrelation()
,
check_collinearity()
,
check_convergence()
,
check_heteroscedasticity()
,
check_homogeneity()
,
check_model()
,
check_outliers()
,
check_overdispersion()
,
check_predictions()
,
check_singularity()