It just allows you to set up sample random sample rates at individual levels. So the hierarchy of Site Intercept is Zone Code > Intercept > Action Set.



There is only ever 1 zone code to a website. Setting the sample there will allow you to change the sampling of all intercepts and action sets on the site.



There can be multiple Intercepts to a zone code. So you can decide that Intercepts A and B need a rate of 50% sampling. But Intercept C only needs 5% sampling.



Same for the action. There can be many Action Sets to an intercept. Setting the action set sample rate allows you to alter the sample rate for one or more actions within an intercept. So- I want on this Intercept 2 different Action Sets with 2 different creatives to display. Which one preforms better? Let's set 1 for a 50% display rate, and let the other one show the other 50% of the time.



It's just different levels of control depending on what your use case is. I strongly suspect you're not going to be getting into Action Set codes unless you're doing A/B testing of some sort.

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