# showPearsonPower

##### Visualisation of the power of a Pearson correlation test

This fuction is useful when conducting power analyses for a Pearson correlation. It draws the sampling distribution of Pearson's *r* assuming a null hypothesis value of *r* and assuming a the hypothetical population value. The probability of making a Type 1 error is also illustrated.

- Keywords
- hplot

##### Usage

```
showPearsonPower(n = 100, rho = 0.3, rNull = 0,
distLabels = c("Null Hypothesis", "Population"),
rhoColor = "green", rhoFill = "green",
rhoAlpha = 0.1, rhoLineSize = 1,
rNullColor = "blue", rNullFill = "blue",
rNullAlpha = 0.1, rNullLineSize = 1,
type2Color = "red", type2Fill = "red",
type2Alpha = 0.1, type2LineSize = 0,
theme = dlvTheme(), alpha = 0.05, digits = 3)
```

##### Arguments

- n
The number of participants.

- rho
The value of the correlation coefficient in the population.

- rNull
The value of the correlation coefficient according to the null hypothesis.

- distLabels
Labels for the two distributions; the first one is the null hypothesis distribution, the second one the alternative distribution.

- rhoColor, rNullColor, type2Color
The border colors of the distributions and the region used to illustrate the Type 2 error probability.

- rhoFill, rNullFill, type2Fill
The fill colors of the distributions and the region used to illustrate the Type 2 error probability.

- rhoAlpha, rNullAlpha, type2Alpha
The alpha (transparency) of the distributions and the region used to illustrate the Type 2 error probability.

- rhoLineSize, rNullLineSize, type2LineSize
The line thicknesses of the distributions and the region used to illustrate the Type 2 error probability.

- theme
The theme to use.

- alpha
The significance level (alpha) of the null hypothesis test.

- digits
The number of digits to round to.

##### Value

A `ggplot`

plot is returned.

##### See Also

##### Examples

```
# NOT RUN {
showPearsonPower();
# }
```

*Documentation reproduced from package userfriendlyscience, version 0.7.2, License: GPL (>= 3)*