nortestTwoWay: Normality Tests for Two-Way Layout

In twowaytests: Two-Way Tests in Independent Groups Designs

Normality Tests for Two-Way Layout

Description

nortestTwoWay performs normality tests including Shapiro-Wilk, Shapiro-Francia, Kolmogorov-Smirnov, Anderson-Darling, Cramer-von Mises, Pearson Chi-square tests, and also assess the normality of each group through plots for two-way layout.

Usage

nortestTwoWay(formula, data, method = c("SW", "SF", "LT", "AD", "CVM", "PT"), 
  alpha = 0.05, plot = c("qqplot", "histogram"), na.rm = TRUE, verbose = TRUE)

Arguments

formula	a formula of the form lhs ~ rhs where lhs gives the sample values and rhs the corresponding two factors.
data	a data frame containing the variables in formula.
method	a character string to select one of the normality tests. "SW": Shapiro-Wilk test, "SF": Shapiro-Francia test, "LT": Lilliefors (Kolmogorov-Smirnov) test, "AD": Anderson-Darling test, "CVM": Cramer-von Mises test, "PT": Pearson Chi-square test.
alpha	the level of significance to assess normality. Default is set to alpha = 0.05.
plot	a character string to select one of the plots including qqplot and histogram. The red line is the density line of normal distribution. If plot is set to NULL, the plot is not returned.
na.rm	a logical value indicating whether NA values should be stripped before the computation proceeds.
verbose	a logical for printing output to R console.

Value

A data frame gives the test results for the normality of each subset via corresponding normality.

Author(s)

Osman Dag, Sam Weerahandi, Malwane Ananda

See Also

gplotTwoWay shapiro.test

Examples

library(twowaytests)
data(alveolar)
nortestTwoWay(cell ~ ovalbumin*treatment, data = alveolar)

twowaytests documentation built on March 31, 2023, 9:26 p.m.