wilcox_TOST {TOSTER}R Documentation

TOST with Wilcoxon-Mann-Whitney tests

Description

A function for TOST using the non-parametric methods of the Wilcoxon-Mann-Whitney family of tests. This function uses the normal approximation and applies a continuity correction automatically.

Usage

wilcox_TOST(
  x,
  ...,
  hypothesis = "EQU",
  paired = FALSE,
  eqb,
  low_eqbound,
  high_eqbound,
  ses = "rb",
  alpha = 0.05
)

## Default S3 method:
wilcox_TOST(
  x,
  y = NULL,
  hypothesis = "EQU",
  paired = FALSE,
  eqb,
  low_eqbound,
  high_eqbound,
  ses = c("rb", "odds", "cstat"),
  alpha = 0.05,
  mu = 0,
  ...
)

## S3 method for class 'formula'
wilcox_TOST(formula, data, subset, na.action, ...)

Arguments

x

a (non-empty) numeric vector of data values.

...

further arguments to be passed to or from methods.

hypothesis

'EQU' for equivalence (default), or 'MET' for minimal effects test, the alternative hypothesis.

paired

a logical indicating whether you want a paired t-test.

eqb

Equivalence bound. Can provide 1 value (negative value is taken as the lower bound) or 2 specific values that represent the upper and lower equivalence bounds.

low_eqbound

lower equivalence bounds (deprecated).

high_eqbound

upper equivalence bounds (deprecated).

ses

Standardized effect size. Default is "rb" for rank-biserial correlation. Options also include "cstat" for concordance probability, or "odds" for Wilcoxon-Mann-Whitney odds (otherwise known as Agresti's generalized odds ratio).

alpha

alpha level (default = 0.05)

y

an optional (non-empty) numeric vector of data values.

mu

number indicating the value around which (a-)symmetry (for one-sample or paired samples) or shift (for independent samples) is to be estimated. See [stats::wilcox.test].

formula

a formula of the form lhs ~ rhs where lhs is a numeric variable giving the data values and rhs either 1 for a one-sample or paired test or a factor with two levels giving the corresponding groups. If lhs is of class "Pair" and rhs is 1, a paired test is done.

data

an optional matrix or data frame (or similar: see model.frame) containing the variables in the formula formula. By default the variables are taken from environment(formula).

subset

an optional vector specifying a subset of observations to be used.

na.action

a function which indicates what should happen when the data contain NAs. Defaults to getOption("na.action").

Details

For details on the calculations in this function see vignette("robustTOST").

Value

An S3 object of class "TOSTnp" is returned containing the following slots:

"TOST"

A table of class "data.frame" containing two-tailed wilcoxon signed rank test and both one-tailed results.

"eqb"

A table of class "data.frame" containing equivalence bound settings.

"effsize"

table of class "data.frame" containing effect size estimates.

"hypothesis"

String stating the hypothesis being tested.

"smd"

List containing information on standardized effect size.

"alpha"

Alpha level set for the analysis.

"method"

Type of non-parametric test.

"decision"

List included text regarding the decisions for statistical inference.

References

David F. Bauer (1972). Constructing confidence sets using rank statistics. Journal of the American Statistical Association 67, 687–690. doi: 10.1080/01621459.1972.10481279.

Myles Hollander and Douglas A. Wolfe (1973). Nonparametric Statistical Methods. New York: John Wiley & Sons. Pages 27–33 (one-sample), 68–75 (two-sample). Or second edition (1999).

See Also

Other Robust TOST: boot_log_TOST(), boot_t_TOST(), boot_t_test(), log_TOST()

Examples

data(mtcars)
wilcox_TOST(mpg ~ am,
data = mtcars,
eqb = 3)

[Package TOSTER version 0.7.1 Index]