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WRS2 (version 1.1-6)

med1way: Heteroscedastic one-way ANOVA for medians.

Description

This function computes a one-way ANOVA for the medians. Homoscedasticity assumption not required. There shouldn't be too many ties.

Usage

med1way(formula, data, iter = 1000, ...)

Value

Returns an object of class med1way containing:

test

F-value of the test statistic

crit.val

critical value

p.value

p-value

call

function call

Arguments

formula

an object of class formula.

data

an optional data frame for the input data.

iter

number of iterations to determine critical value.

...

currently ignored.

Details

Evaluating the test statistic using the df proposed in the literature can result in the actual level being less than the nominal level, (i.e., around 0.02-0.025 when testing at the 0.05 level and the sample size is small). A better strategy is to simulate the critical value and computing the p-value accordingly, as implemented in this function.

References

Wilcox, R. (2012). Introduction to Robust Estimation and Hypothesis Testing (3rd ed.). Elsevier.

See Also

t1way,t1waybt, Qanova

Examples

Run this code
set.seed(123)
med1way(libido ~ dose, data = viagra, iter = 3000)

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