Random Number Generator (RNG)
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Participation Rewards

How are participation rewards different from traditional dividend payments?

GPOS introduces a number of significant changes to the old method of dividing the Peerplays rake between all token holders relative to how many tokens they hold.
The biggest change is that the percentage of the rake is based on the total of all GPOS vested balances, and not the cumulative value of all PPY in circulation. This gives the opportunity for regular voters to get a larger share of the rake than before by virtue of other unreliable voters.

I'm confused, just how exactly are my rewards calculated?

At first the new formula for calculating your estimated reward percentage can be a bit confusing; this example should help:
If you have a GPOS balance of 1,000PPY, and have voted recently, so you have qualified for a 100% reward, and the total GPOS balance on the blockchain is 4,000,000PPY when the rake is distributed, then your percentage of the rake would be:
(1,000 / 4,000,00) * 0.025%
What you'll actually receive as a dividend is based on the monthly rake, so if the rake is 100,000PPY then you'd receive 100,000 * 0.025% = 25PPY.