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Bitcoin => Bitcoin Discussion => Topic started by: tucenaber on March 21, 2012, 08:45:20 AM



Title: A method to get higher precision in total network hashrate
Post by: tucenaber on March 21, 2012, 08:45:20 AM
I was thinking that to get better accuracy when estimating network hashrate you could exploit the fact that the big pools publicise their hashrate with almost perfect accuracy, i.e. the exact number of shares. If you trust their numbers you could get a lower variance if you counted the pools' blocks separately.

If N(t) is the number of blocks minted up to time t, then ΔN(t)/Δt is the best estimation of network hashrate λ in the period Δt, which has variance λ/Δt. But if we express it as a sum of unknown and known hashrates:

N(t) = N'(t) + N''(t) where N' has the unknown rate λ' and N'' has known rate λ'', then Var( N(t)/Δt ) = Var(N'(t)/Δt + N''(t)/Δt) = λ'/Δt + 0

According to http://blockchain.info/pools (http://blockchain.info/pools) we could reduce the variance by half by using the three largest pools, and by more than 75% by using the ten largest pools.

My question is, which pools can you trust to give correct numbers?


Title: Re: A method to get higher precision in total network hashrate
Post by: RoloTonyBrownTown on March 21, 2012, 10:09:51 AM


N(t) = N'(t) + N''(t) where N' has the unknown rate λ' and N'' has known rate λ'', then Var( N(t)/Δt ) = Var(N'(t)/Δt + N''(t)/Δt) = λ'/Δt + 0



Er, yeah!  That's totally what I was just about to say...


Title: Re: A method to get higher precision in total network hashrate
Post by: Liberate on March 21, 2012, 05:07:12 PM
You can trust no one but yourself.


Title: Re: A method to get higher precision in total network hashrate
Post by: DeathAndTaxes on March 21, 2012, 05:18:20 PM
p2pool.  No way to fake those shares as they are verified by each node.

Other pools it comes down to a judgement call.  Smaller pools might have more reason to lie (to attract more members) and you get biggest bang for the back looking at larger pools.  I wouldn't take stats from Bitclockers, ABCPool, or any >100% PPS.

Likely deepbit, slush, BTC Guild, EMC, and p2pool should be enough data points.


Title: Re: A method to get higher precision in total network hashrate
Post by: P4man on March 21, 2012, 05:36:26 PM
Nitpick: the hashrate that pools publish is also just an estimate. Granted, its based on the number of shares, not the number of blocks, so it should be a lot more accurate.

Anyway, for calculating network hashrate, I dont see a reason to disbelieve any of the big pools