ss.aipe.cv.sensitivity: Sensitivity analysis for sample size planning given the...

In MBESS: The MBESS R Package

Sensitivity analysis for sample size planning given the Accuracy in Parameter Estimation approach for the coefficient of variation.

Description

Performs sensitivity analysis for sample size determination for the coefficient of variation given a population coefficient of variation (or population mean and standard deviation) and goals for the sample size procedure. Allows one to determine the effect of being wrong when estimating the population coefficient of variation in terms of the width of the obtained (two-sided) confidence intervals. The values of True.C.of.V and Estimated.C.of.V should be positive.

Usage

ss.aipe.cv.sensitivity(True.C.of.V = NULL, Estimated.C.of.V = NULL,
width = NULL, degree.of.certainty = NULL, assurance=NULL, certainty=NULL, 
mean = 100, Specified.N = NULL, conf.level = 0.95, 
G = 1000, print.iter = TRUE)

Arguments

True.C.of.V	population coefficient of variation
Estimated.C.of.V	estimated coefficient of variation
width	desired confidence interval width
degree.of.certainty	parameter to ensure confidence interval width with a specified degree of certainty (must be NULL or between zero and unity)
assurance	the alias for degree.of.certainty
certainty	an alias for degree.of.certainty
mean	Some arbitrary value that the simulation uses to generate data (the variance of the data is determined by the mean and the coefficient of variation)
Specified.N	selected sample size to use in order to determine distributional properties of at a given value of sample size (not used with Estimated.C.of.V)
conf.level	the desired degree of confidence (i.e., 1-Type I error rate).
G	number of generations (i.e., replications) of the simulation
print.iter	to print the current value of the iterations

Details

For sensitivity analysis when planning sample size given the desire to obtain narrow confidence intervals for the population coefficient of variation. Given a population value and an estimated value, one can determine the effects of incorrectly specifying the population coefficient of variation (True.C.of.V) on the obtained widths of the confidence intervals. Also, one can evaluate the percent of the confidence intervals that are less than the desired width (especially when modifying the degree.of.certainty parameter); see ss.aipe.cv)

Alternatively, one can specify Specified.N to determine the results at a particular sample size (when doing this Estimated.C.of.V cannot be specified).

Value

Data.from.Simulation	list of the results in matrix form
Specifications	specification of the function
Summary.of.Results	summary measures of some important descriptive statistics

Note

Returns three lists, where each list has multiple components.

Author(s)

Ken Kelley (University of Notre Dame; [e-mail])

See Also

cv, ss.aipe.cv

MBESS documentation built on Oct. 26, 2023, 9:07 a.m.