DemographicTable (version 0.2.2)

pval_shapiro: $p$-value from modified Shapiro-Wilk Normality Test

Description

Obtain $p$-value from shapiro.test, taking into consideration of several exceptions.

Usage

pval_shapiro(x, CLT = FALSE, ...)

Value

Function pval_shapiro() returns a double scalar.

Arguments

x

double vector

CLT

logical scalar, whether to allow the use of Central Limit Theorem, default FALSE

...

additional parameters, currently not in use

Details

Function pval_shapiro() provides a pseudo $p$-value for several exceptions of shapiro.test, serving as a criteria of whether robust statistics/tests need to be used

length(x) < 3L

returns $p=0$, indicating that robust methods are needed.

length(x) > 5e3L

returns $p=1$, indicating that no robust method is needed. For such large sample size, robust methods could be too slow.

CLT & length(x) > 30L

returns $p=1$, indicating that no robust method is needed because of the use of Central Limit Theorem.

all x values are identical (or all.equal, to be implemented in future release)

returns $p=0$, indicating that robust methods are needed.

Otherwise

use the $p$-value from shapiro.test.

Examples

rnorm(5) |> pval_shapiro()
airquality |>
 with(expr = split(Ozone, f = Month)) |>
 sapply(FUN = pval_shapiro)