# pwr.f2.test

##### Power calculations for the general linear model

Compute power of test or determine parameters to obtain target power (same as power.anova.test).

- Keywords
- htest

##### Usage

`pwr.f2.test(u = NULL, v = NULL, f2 = NULL, sig.level = 0.05, power = NULL)`

##### Arguments

- u
degrees of freedom for numerator

- v
degrees of freedomfor denominator

- f2
effect size

- sig.level
Significance level (Type I error probability)

- power
Power of test (1 minus Type II error probability)

##### Details

Exactly one of the parameters 'u','v','f2','power' and 'sig.level' must be passed as NULL, and that parameter is determined from the others. Notice that the last one has non-NULL default so NULL must be explicitly passed if you want to compute it.

##### Value

Object of class '"power.htest"', a list of the arguments (including the computed one) augmented with 'method' and 'note' elements.

##### Note

'uniroot' is used to solve power equation for unknowns, so you may see errors from it, notably about inability to bracket the root when invalid arguments are given.

##### References

Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Hillsdale,NJ: Lawrence Erlbaum.

##### Examples

```
# NOT RUN {
## Exercise 9.1 P. 424 from Cohen (1988)
pwr.f2.test(u=5,v=89,f2=0.1/(1-0.1),sig.level=0.05)
# }
```

*Documentation reproduced from package pwr, version 1.2-2, License: GPL (>= 3)*