View source: R/uncondPower2x2.R
uncondPower2x2 | R Documentation |
The function Power2x2
and SS2x2
calculates the power or sample size for any 2x2 test, while the function uncondPower2x2
calculates power for only tests supported by
uncondExact2x2Pvals
.
Power2x2(n1, n2, theta1, theta2, alpha, pvalFunc, ...) uncondPower2x2(n1,n2, theta1, theta2, alpha, ...) SS2x2(theta1, theta2, alpha, pvalFunc, power=0.90, n1start=10, increaseby=1, n2.over.n1=1, maxiter=50, printSteps=TRUE, ...)
n1 |
sample size in group 1 |
n2 |
sample size in group 2 |
theta1 |
probability of success in group 1 |
theta2 |
probability of success in group 2 |
alpha |
significance level |
pvalFunc |
function that inputs x1,n1,x2,n2 and outputs a p-value. |
power |
target power |
n1start |
value of n1 for first iteration |
increaseby |
positive integer, how much to increase n1 by for each iteration |
n2.over.n1 |
ratio of n2/n1 |
maxiter |
maximum number of iterations |
printSteps |
logical, should the power and sample size be printed after each iteration? |
... |
arguments passed to |
The function Power2x2
is a very simple function
to calculate power. It calculates power where rejection is when the p-value from pvalFunc
is less than or equal to alpha
. The function SS2x2
repeatedly calls Power2x2
as it increases the sample size, stopping when
the power is greater than 'power'
.
The function uncondPower2x2
is similar except the
p-values are calculated by uncondExact2x2Pvals
.
the power functions return only the power. The sample size function returns a list of class 'htest.power'.
For power and sample size for conditional exact tests (e.g., Fisher's exact tests) see power2x2
and ss2x2
. For power for the boundary-optimized rejection region (BORR) test see powerBorr
.
library(exact2x2) Power2x2(3,4,.1,.9,0.025, pvalFunc= function(x1,n1,x2,n2){ boschloo(x1,n1,x2,n2, alternative="greater", or=1,tsmethod="central", midp=TRUE)$p.value } ) ## ## Not run: SS2x2(.1,.9,0.025, n1start=5, pvalFunc= function(x1,n1,x2,n2){ boschloo(x1,n1,x2,n2, alternative="greater", or=1,tsmethod="central", midp=TRUE)$p.value } ) ## End(Not run)
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