I am using beta regression because I am trying to predict percentages (response and dropout rates) of surveys.

My aim is now to come up with a final model (I have many different variables and want to reduce them to a final model). I wanted to do that by using the "stepAIC" function.

Unforunately, I get the following error message when I try to do the latter:

**Error in UseMethod("extractAIC") :**

no applicable method for 'extractAIC' applied to an object of class "betareg"

no applicable method for 'extractAIC' applied to an object of class "betareg"

Can anyone explain what this means?

My R code was:

Code:

```
libary (MASS)
model_with_all_possible_variables <- betareg()
stepAIC(model_with_all_possible_variables)
```

Can someone offer me some advice as to how to find the best final model, please? I'd be really beyond grateful. I am aware that the lrt test can be used for beta regression, but I was wondering whether there is a way to use the stepAIC-approach (or some other method)? How would you guys go about it?

Best,

Amanda