Hello everyone,

I am new to R and RStudio and would like to know if I am using the formula for the Friedman test correctly. I am using the `stats`

package and the `friedman.test`

function.

My data are repeated measures of difference scores in reaction times for human subjects on a computer task. Each subject has a specific difference score at each point in time. Hence, I believe I have :

- A dependent variable : the difference scores (Score.D)
- An independent variable : the times of measurement (three different points in time)
- A conditioning or blocking variable : the identity (ID) of the participants in the study

Would you say that is correct ? If it is, then the formula should be :

`friedman.test(Score.D ~ Time | ID) `

Wouldn't you agree ?