They mean that it's fraud to mislead people by gaming their assumptions about performance indicators. Specifically, they're saying that paying for one kind of

They mean that it's fraud to mislead people by gaming their assumptions about performance indicators. Specifically, they're saying that paying for one kind of popularity (e.g., sales of widgets or good reviews on Amazon.com) is fraud when that popularity is meant to trick people into believing that it implies a subtly different kind of popularity (e.g., sales of widgets from independent third parties or good reviews on Amazon.com from unbiased reviewers).