Onsite personalization rules revenue can be shown in three different ways, View through, Click through and Direct revenue.
Changing the attribution model is done using the select box above the rules performance section of the dashboard.

In view through revenue model, any purchase performed after the rule has triggered for the user during the same session is attributed to the rule. This is useful for example when measuring the general effect of a rule by comparing the view through revenue to the rule control group (which hides the rule output for random users matching the same segment).

This mode measures revenue from purchases which occurred after the visitor was exposed to the rule output, clicked on it and then purchased.

Direct Revenue attempts to measure items purchased directly as a result of the rule engagement. It is particularly useful for measuring rules which promote specific products or product categories.
Items purchased are considered direct revenue if they were viewed in the next 2 page views after a click on the rule content or they belong to a category which the rule content points to directly (or its subcategory).