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Bitcoin => Bitcoin Discussion => Topic started by: evoorhees on October 01, 2011, 08:20:45 PM



Title: Hash rate question - WTF variance?
Post by: evoorhees on October 01, 2011, 08:20:45 PM

http://img13.imageshack.us/img13/3338/networkc.gif

This is the familiar screenshot taken from Bitcoinwatch.com.

Why would the range oscillate within about 1.5 terahashes for a few days, then soar almost 3 terahashes in one day? That is an increase of like 35%

I would like some explanation from any smart people out there... you would think the rate would follow a much more normalized 24-hr pattern. Is it a week vs. weekend thing? wtf?


Title: Re: Hash rate question - WTF variance?
Post by: elggawf on October 01, 2011, 10:13:49 PM
As I understand it the "hash rate" is a guess based on the frequency of blocks, and because the blocks are mostly random intervals that's why the hash rate swings all over.


Title: Re: Hash rate question - WTF variance?
Post by: evoorhees on October 02, 2011, 05:27:45 AM
This has indeed happened before, and it will happen again. Like you, I wonder why.

We used to explain it by saying "mystery miner", kind of like "the manipulator" of today.

Oh I wasn't saying it's a new phenomenon, it happens all the time. The pic I posted is just a good example of it.


Title: Re: Hash rate question - WTF variance?
Post by: maaku on October 02, 2011, 07:13:02 AM
I would expect about 9% variance due simply to random chance if this metric were calculated with a sliding window of one day. I would expect even larger variance if that sliding window were smaller (as appears to be the case here).

Note that there is also a strong periodic daily cycle causing swings up and down, and almost certainly due to those miners turning their machines off at night.