t1way: A heteroscedastic one-way ANOVA for trimmed means.

In WRS2: A Collection of Robust Statistical Methods

A heteroscedastic one-way ANOVA for trimmed means.

Description

The t1way function computes a one-way ANOVA on trimmed means. Homoscedasticity assumption not required. It uses a generalization of Welch's method. Corresponding post hoc tests can be performed using lincon.

Usage

t1way(formula, data, tr = 0.2, alpha = 0.05, nboot = 100, ...)
lincon(formula, data, tr = 0.2, alpha = 0.05, method = "hochberg", ...)

Arguments

formula	an object of class formula.
data	an optional data frame for the input data.
tr	trim level for the mean.
alpha	alpha level for CI computation.
nboot	number of bootstrap samples for effect size CI computation.
method	method to correct the p-value (see p.adjust)
...	currently ignored.

Details

In the post hoc computations, confidence intervals and p-values are adjusted to control FWE. The default for the p-values is to use Hochberg's 1988 sharper Bonferroni procedure.

Value

t1way returns an object of class "t1way" containing:

test	value of the test statistic (F-statistic)
df1	degrees of freedom
df2	degrees of freedom
p.value	p-value
effsize	explanatory measure of effect size
effsize_ci	boostrap effect size CI
call	function call

lincon returns an object of class "mcp1" containing:

comp	inference for all pairwise comparisons
fnames	names of the factor levels

linconv2 returns an object of class "linconv2" containing:

References

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

See Also

med1way,t1waybt

Examples

set.seed(123)
t1way(libido ~ dose, data = viagra)

## post hoc tests
lincon(libido ~ dose, data = viagra)

WRS2 documentation built on March 19, 2024, 3:08 a.m.