Bitcoin Forum

Hi.

Where or How can I know, when difficulty gonna change (up or down) BEFORE it happens??

Thanks

You can get lots of cool information from here: http://blockexplorer.com/q

Next target  (http://blockexplorer.com/q/nextretarget)will have this difficulty (http://blockexplorer.com/q/estimate).

ty so much

Divide the current block number by 2016.  Subtract the remainder from 2016.  Your answer is the number of blocks between now and the next retarget.

Actually to be more precise (a tool could be created but it's not really a precise moment in time to be predicted), you can do the following on http://blockexplorer.com/q
- Get the current block number: http://blockexplorer.com/q/getblockcount
- Get the next retarget block number: http://blockexplorer.com/q/nextretarget
- Get the current average interval: http://blockexplorer.com/q/interval

For example now, it's block 128249, difficulty change in (129023 - 128249) = 774 blocks that take on average 504 seconds => 108.4 hours => 4.515 days.

According to Wolfram Alpha (http://www.wolframalpha.com/input/?i=3%3A25%3A42+am+EEST++|++Friday%2C+June+3%2C+2011+%2B+4.515+days), the exact difficulty change will be on 3:47:18 pm EEST  |  Tuesday, June 7, 2011.

I'll bet you 1 BTC that the change does not happen during that second.    :)

So how much money is there to be made by predicting the direction and time of the next difficulty change, assuming it has a straightforward effect on price, and buying/selling loads of coins?

Not straightforward at all.  The USD to BTC ratio and the difficulty most likely form a complex system (http://en.wikipedia.org/wiki/Lotka–Volterra_equation).

Well, of course it won't happen on that second, I wouldn't counter-bet, the chances are worse than me finding a whole block with my CPU today. New estimate: 2:53:48 am EEST  |  Tuesday, June 7, 2011

Notice it has decreased by 12 hours over a period of a day. This is due to increased mining activity and/or localized luck ratio in finding blocks. It might not even happen on the June 7th.

Could anyone build a better BitcoinX profit tool that takes into account difficulty changes during the given period?

According to the weak efficient market hypothesis, none. Everybody is able to take the next difficulty change into account when pricing, so they already set their prices appropriate to it.

https://secure.wikimedia.org/wikipedia/en/wiki/Efficient_market_hypothesis

of course but I won't share for free.   ;)

all it really takes is a field for guessing price and difficulty changes as percentages with the default being the historical rates.

thanks for the info