segmentOverrides
Use this parameter to specify different traffic splits for one or more audience segments. A segment is a portion of your audience that share one or more characteristics. Examples could be Chrome browser users, users in Europe, or Firefox browser users in Europe who also fit other criteria that your application collects, such as age.
This parameter is an array of up to six segment override objects. Each of these objects specifies a segment that you have already created, and defines the traffic split for that segment.