Quote from: Meni Rosenfeld on September 05, 2011, 07:30:14 PM

*sigh*

I don't mean to annoy you, just telling you the practical experience from the point of view of the miner. I'm glad now, instead of PPLNS, we're considering the double geometric method, which I assume is similar to the current method. Is there a post explaining it?

Quote from: Meni Rosenfeld on September 05, 2011, 07:30:14 PM

Quote from: cengique on September 05, 2011, 06:27:23 PM

Especially in the long blocks, people hop-off to leave and mine on other pools.

They don't gain anything from doing that. The fact that the round was long does not affect the payouts of futures shares they submit.

I agree with you. I didn't claim they have a gain from hopping off the pool. All I said is that people get tired when the block gets long and decide to mine on other pools. Maybe it's not the only reason, but I often see the total hash rate fall from 80 to 60GH/s over the course of a long block. In the last monster block, I remember we fell to about 50 GH/s. Then it becomes important that the scoring method makes people stay in the pool. If you didn't have that I assume more people would be leaving. I don't have a way of proving this, though.

Quote from: Meni Rosenfeld on September 05, 2011, 07:30:14 PM

Quote from: cengique on September 05, 2011, 06:27:23 PM

If they can guarantee payment by contributing in the last N shares without any decay, they can do this without loss.

They don't know when the round will end, so they don't know which shares are the last N. There's decay, but it's a step function rather than exponential.

Ok, I wasn't completely correct, there is decay because as there are new shares mined, the window slides and your shares will go down. However, consider the following disadvantages of using the PPLNS method:

1) In the first N shares of a block, PPLNS is equivalent to PPS.
In the mineco.in example, N was 750k shares, and with Eclipse's hash rate, it would be reached in about 17 hours. So if a block is shorter than that, it would practically be found using PPS method.

Inaba: Could you add the average values at the bottom of the block stats table? It would ne nice to know our actual average shares/block and also their standard deviation maybe.

2) After the pool has mined N shares for a block, during the time it takes to mine N shares by the pool, one can hop in for n << N hours and would have (N-n) hours without any decay in reward.
They do not gain anything from doing this, but the pool's hash rate is reduced. If they switch to a giant pool, they get steady payout.

3) In a long block, if many people follow the idea in (2), the pool's hash rate can drop to zero, stopping the rewards from decaying and the pool never succeeding in finding the block.
Obviously this is an extreme case, but if the hash rate drops significantly it will create a similar scenario where the pool becomes "cursed".

Quote from: Meni Rosenfeld on September 05, 2011, 07:30:14 PM

Quote from: cengique on September 05, 2011, 06:27:23 PM

The geometric method, in addition to being hopping-proof, also encourages the miners to stay put in the pool.

No, it does not. For the past shares they will get the same reward whether they stay or quit. For future shares they will get the same reward whether they mined previously or not.

I think there's a misconception that decay only happens when you leave the pool. But past shares decay the same way whether you're in or out. The reward for future shares is independent.

Thanks for the explanation, it does help to understand the probabilities better. You are right, except in my case (2) above, where there will be a short time without decay for the past shares. Although, I don't challenge the fact that your reward will increase in both methods if you mine continuously.