Segment ​Samples

By clicking on the three dots and clicking "Create sample" you can create a specific sub-segment by creating a sample size. E.g. If 1000 users are in a segment and you create a sample of 100, you will create a subsegment with 100 randomized users of the previous segment. This can be useful to test campaigns on a smaller sample size.
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​Alternatively here is a video explaining the "Segments" feature:
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