pow_prop: Creates a plot or a table for the type I error rate and power...

Description Usage Arguments Value Author(s) See Also

Description

It creates a plot or a table for the sample size, type I error rate, and power versus standard deviation. If desired, it may represent several actual expected value differences for comparison.

Usage

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pow_prop(delta = 0, Delta, sd, test = 1, alpha = 0.05, beta = 0.2, prop = c(0.1, 1),
         adj = F, rule = F, nbound = 500, simu = 10000, create = "plot")

Arguments

delta

Number. Expectation difference of two samples.
If you select a Test for superiority/ difference then select 'delta = 0'.
Only if you select a Test for non-inferiority you can select 'delta != 0'.
Attention: If you chose 'test = 1' and 'delta != 0', the test for non-inferiority will
automatically be applied.
If not specified, delta is set to 0.

Delta

Number/ vector of numbers. Relevant difference of expected values in the alternative hypothesis.
A maximum of five different values are possible if you choose create = "tab".

sd

Number. Assumed standard deviation of the data.
Used to calculate the originally planned number of cases.

test

Number. What type of hypothesis test should be performed. One-sided (Superiority/
Non-Inferiority test) or two-sided (Test for difference).
One-sided (test = 1): Superiortity H0: mu_x - mu_y <= 0 vs. H1: mu_x - mu_y > 0
Non-Inferiority H0: mu_x - mu_y >= delta vs. H1: mu_x - mu_y < delta
Two-sided (test = 2): Difference H0: |mu_x - mu_y| = 0 vs. H1: |mu_x - mu_y| != 0
Attention: Choice of delta. (see delta)
If not specified, the one-Sided Test (Superiority/ Non-Inferiority Test) is used.

alpha

Number. Desired alpha-level of the test.
If not specified, alpha is set to 0.05.

beta

Number. Acceptable beta error of the test.
If not specified, beta is set to 0.2.

prop

Two numbers/ Vector of numbers. Timing of the internal pilot study depending on the originally
planned sample size.
Two numbers must be passed, the smallest and largest timing of the internal pilot study.
The plot is displayed for the interval of these values.
If two values are transferred, a sequence is automatically defined.
If several values are transferred, these are interreted as a sequence.

adj

Logical. Should the one-sample variance, calculated in the internal pilot study, be adjusted?

rule

Logical. Should the sample size adjustment rule be applied by Wittes and Brittain?

nbound

Number. Upper limit of the sample size.
Attention: Only if you choose nbound can a suitable standard deviation range for the plots
be calculated automatically.
If no nbound are defined then a standard deviation range must be chosen (see sd_ber).

simu

Number. How many simulations should be performed?
If not specified, simu is set to 10000.

create

"plot" if a plot is to be returned.
"tab" if a table is to be returned.

Value

It returns a plot.

Author(s)

Csilla van Lunteren

See Also

pow
ggplot2


vanLunteren/plan_norm documentation built on May 20, 2019, 12:32 p.m.