Hi, I am trying to setup experiment with GrowthBook. I have setup an experiment https://app.growthbook.io/experiment/exp_19g61tlmreelej When I try to fetch the value in my test, it always return the same value. Is it because I did not set a user ID with GrowthBook yet? would all the anonymous user always get the same value in experiment?

Yes. Growthbook hashes based upon the assignment attribute and the feature key. If you don't change the assignment attribute ever then the hash will be the same and it will get the same value.

what would be the suggested way for me to handle anonymous user? We have a large amount of pages that user will stay anonymous

You should target your experiment then to an anonymous id

would that be deviceId?

for GA4? Yes.

Sorry I was referring deviceId in here

You can check out your datasource page to see if both anonymous_id and user_id have been set up.

Thanks, that sounds like the plan

Yes as long as that attribute gets set when Growthbook gets instantiated.

I see, so I will have to set it, otherwise it will not work? I was using google optimize and they set one on their own

There is a video here that explains moving over from google optimize: https://docs.growthbook.io/guide/GA4-google-analytics