(http://en.wikipedia.org/wiki/Granger_causality)

Pairwise Granger Causality Tests

Sample: 8/16/2010 11/22/2013

Lags: 4

Null Hypothesis: Obs. F-Statistic Prob.

H

_{0}A) LOG(HASH) does not Granger Cause LOG(PRICE) 1182 0.30372 0.8756

H

_{0}B) LOG(PRICE) does not Granger Cause LOG(HASH) 8.96203 4.E-07

What this says is that A) we Fail to reject the Null hypothesis that a change in hash does Not cause a change in price, because the F-statistic is very small. This means that the statement "hash does not change price" is likely very true to a high degree of certainty.

On the other hand in B) we see that the F-statistic is very high (significant) for the Null hypothesis that a change in price does Not change the hashrate. This means we should reject this null hypothesis with a high degree of certainty, and accept the alternate hypothesis: "A change in prices DOES cause a change in hash".

(I used natural log of each variable to normalize them a bit as they both have increased very rapidly lately. If you don't use the log, the results are even MORE significant).

This sort of throws a wrench in the labor theory of value in mining bitcoins, but I think the debate isn't 100% over yet on that front.

cheers.