Hi @yuning.yan - my apologies! I wasn’t getting notifications for this for some reason. I usually get emails, but didn’t see anything come through.
It is certainly possible to integrate your Segment Cloud-mode data with Amplitude Experiment. The key is to ensure that The same User ID and Device ID are used between Segment and Amplitude because we bucket users based on their Amplitude ID. Device_id (Anonymous ID) is generated by Segment and stored in a Segment cookie. If the cookie is set, try retrieving ID. Else, create a new one. Here’s an example of how you can retrieve the Segment Anonymous ID: https://segment.com/docs/connections/sources/catalog/libraries/website/javascript/identity/#retrieve-the-anonymous-id
The code snippet on this page also contains an example of how to pull UserId and anonymousId if present: https://segment.com/docs/guides/how-to-guides/collect-pageviews-serverside/
If you’d like, you can also request a Demo to learn more about Amplitude Experiment: https://info.amplitude.com/experiment-demo
Apologies again for the late reply and let me know if you have any questions!