# n_dist.ChiSquare: Distribution of the Sample Size In blindrecalc: Blinded Sample Size Recalculation

 n_dist,ChiSquare-method R Documentation

## Distribution of the Sample Size

### Description

Calculates the distribution of the total sample sizes of designs with blinded sample size recalculation for different values of the nuisance parameter or of n1.

### Usage

``````## S4 method for signature 'ChiSquare'
n_dist(
design,
n1,
nuisance,
summary = TRUE,
plot = FALSE,
allocation = c("exact", "approximate"),
...
)
``````

### Arguments

 `design` Object of class `ChiSquare` created by `setupChiSquare`. `n1` Either the sample size of the first stage (if `recalculation = TRUE` or the total sample size (if `recalculation = FALSE`). `nuisance` Value of the nuisance parameter in (0,1). For the Chi-Squared test this is the overall response rate. `summary` Is a summary of the sample size distribution desired? Otherwise, a vector with sample sizes is returned. `plot` Should a plot of the sample size distribution be drawn? `allocation` Whether the allocation ratio should be preserved exactly (`exact`) or approximately (`approximate` or `kf_approx`). `appproximate` uses the unrounded calculated sample size in the sample size recalculation, `kf_approx` rounds the sample size to the next integer. `...` Further optional arguments.

### Details

Only sample sizes that occur with a probability of at least 0.01 are considered.

The method is only vectorized in either `nuisance` or `n1`.

### Value

Summary and/or plot of the sample size distribution for every nuisance parameter and every value of n1.

### Examples

``````  d <- setupChiSquare(alpha = 0.025, beta = 0.2, r = 1, delta = 0.2)
n_dist(d, n1 = 20, nuisance = 0.25, summary = TRUE, plot = FALSE)

``````

blindrecalc documentation built on Oct. 4, 2023, 5:06 p.m.