onewaytests (version 3.1)

ap.test: Approximate F Test

Description

ap.test performs approximate F test. This test assumes that the data within each group are normally distributed and offers a robust alternative to one-way ANOVA when heteroscedasticity is present. The test statistic follows an approximate F-distribution. Especially for small samples, this test provide better control of the type I error rate.

Usage

ap.test(formula, data, alpha = 0.05, na.rm = TRUE, verbose = TRUE)

Value

A list with class "owt" containing the following components:

statistic

the approximate F test statistic.

parameter

the parameter(s) of the approximate F distribution of the test statistic.

p.value

the p-value of the test.

alpha

the level of significance to assess the statistical difference.

method

the character string "Approximate F Test".

data

a data frame containing the variables in which NA values (if exist) are removed.

formula

a formula of the form lhs ~ rhs where lhs gives the sample values and rhs the corresponding groups.

Arguments

formula

a formula of the form lhs ~ rhs where lhs gives the sample values and rhs the corresponding groups.

data

a tibble or data frame containing the variables in formula.

alpha

the level of significance to assess the statistical difference. Default is set to alpha = 0.05.

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.

Author

Merve Kasikci

References

Asiribo, O., Gurland, J. (1990). Coping with Variance Heterogeneity. Communications in Statistics-Theory and Methods, 19:11, 4029-4048.

Examples

library(onewaytests)

ap.test(Sepal.Length ~ Species, data = iris)

out <- ap.test(Sepal.Length ~ Species, data = iris, verbose = FALSE)
summary(out)
paircomp(out)