The translation of the above is that the ratio of certification to salary does not equal (or have much bearing on) the ratio of person to their experience level.
So in response to the idea of an ITIL v2 Foundation showing MORE than a v3 Master is just a "feature" (problem?) with surveys. We don't know any more about the people filling that out.
So whoever had that v2 Foundation may have had other certifications as well or lots of experience making their salary higher. (or just a cooler employer?)
The v3 Master may have drawn the short stick on those different pieces.
Like all statistics, your mileage may vary!
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