Normality test of a numeric vector

Applies a Shapiro-Wilks test to a numeric vector, and plots the qq plot and the histogram.

residuals_diagnostics(residuals, predictions)

Arguments

residuals

Numeric vector, model residuals.

predictions

Numeric vector, model predictions.

Value

A list with four slots:

• /item w W statistic returned by shapiro.test(). /item p.value p-value of the Shapiro test. /item interpretation Character vector, one of "x is normal", "x is not normal". /item plot A patchwork plot with the qq plot and the histogram of x.

Details

The function shapiro.test() has a hard limit of 5000 cases. If the model residuals have more than 5000 cases, then sample(x = residuals, size = 5000) is applied to the model residuals before the test.

See also

ggplot,aes,geom_qq_line,ggtheme,labs,geom_freqpoly,geom_abline plot_annotation

Examples

if(interactive()){

 residuals_diagnostics(
   residuals = runif(100),
   predictions = runif(100)
 )

 }