Full Pay doesn't necessarily mean Positive VP and vice versa.
Examples - 9/6 JoB is FP but isn't positive.
10/7/80 DB is positive but isn't FP.
From the vpFREE FAQ:
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3. What is a full-pay VP machine? - A machine that has the best pay schedule
for a particular VP Game that can be found in any quantity in casinos.
4. What is a positive VP machine? - It is a machine with a pay table that will
return more than 100% over the long term when played with perfect strategy.
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