Enhanced model diagnostics

Extends checkModel() with additional soft checks that flag potential numerical issues before computationally expensive diagnostics are executed. The helper mirrors the warnings used throughout the package and retains the original return semantics for backward compatibility.

Usage

checkModelEnhanced(model, data = NULL)

Arguments

model

Fitted model supplied to subsequent diagnostics.

data

Optional data.frame used when fitting model. When provided it enables multicollinearity checks via performVIFDiagnostic().

Value

Invisibly returns model after issuing any relevant warnings.

Details

The function warns when residual degrees of freedom fall below six, when a near-perfect fit is detected (R\(^2 > 0.999\)), or when variance inflation factors (VIFs) exceed 10. The latter threshold follows the regression diagnostics literature (Belsley et al., 1980).

References

Belsley, D. A., Kuh, E., & Welsch, R. E. (1980). Regression Diagnostics: Identifying Influential Data and Sources of Collinearity. Wiley.

See also

checkModel(), performVIFDiagnostic(), validateTestInputs()

Examples

data(mtcars)
fit <- stats::lm(mpg ~ wt + hp, data = mtcars)
checkModelEnhanced(fit)