# powerPaired2x2: Power for exact McNemar's test In exact2x2: Exact Tests and Confidence Intervals for 2x2 Tables

## Description

Calculate the power for the exact McNemar's test (i.e., `exact2x2` with `paired=TRUE`) given the number of pairs and the probability of a positive response only in the test individual in the pair (pb), and the probability of a positive response only in the control individual in the pair (pc).

## Usage

 ```1 2 3``` ```powerPaired2x2(pb, pc, npairs, sig.level = 0.05, alternative = c("two.sided", "one.sided"), strict = FALSE, nullOddsRatio = 1, errbound = 10^-6, ...) ```

## Arguments

 `pb` probability of a (0,1) response for a pair, meaning negative response in the control individual and a positive response in the test individual `pc` probability of a (1,0) response for a pair, meaning positive response in the control individual and a negative response in the test individual `npairs` the number of pairs `sig.level` significance level (also called alpha-level) `alternative` either 'one.sided' or 'two.sided' (see `tsmethod` for two-sided method) `strict` use strict interpretation in two-sided case (i.e., TRUE allows rejections in the 'wrong' direction) `nullOddsRatio` null odds ratio, internally passed to `or` argument of `exact2x2` with `paired=TRUE` `errbound` error bound, `errbound=0` does exact calculation, when `errbound>0` then speed up calculations by not calculating outcomes at either extreme with tail probabilities less than errbound/2 which may underestimate power by at most errbound. `...` arguments passed to `exact2x2` (except these arguments cannot be passed this way: `or`, `alternative`, `conf.int`, `paired`, `plot`)

## Details

When `alternative='one.sided'` then the test automatically picks the side that is most powerful.

## Value

An object of class 'power.htest' with elements:

 `power` power `npairs` number of pairs `pb` probability of a (control,test)=(0,1) response for a pair `pc` probability of a (control,test)=(1,0) response for a pair `sig.level` significance level or alpha-level `alternative` either one-sided or two-sided `nullOddsRatio` null odds ratio (or boundary between null and alternative for one-sided tests) `note` notes about calculation (e.g., errbound value) `method` description of method

## Examples

 `1` ```powerPaired2x2(.5,.3,npairs=20) ```

### Example output

```Loading required package: exactci

Power for McNemar's Exact Test

power = 0.1191185
npairs = 20
pb = 0.5
pc = 0.3
sig.level = 0.05
alternative = two.sided
nullOddsRatio = 1

NOTE: errbound= 1e-06
```

exact2x2 documentation built on Dec. 11, 2021, 9:43 a.m.