Bitcoin Forum
December 03, 2016, 05:49:21 PM *
News: Latest stable version of Bitcoin Core: 0.13.1  [Torrent].
 
   Home   Help Search Donate Login Register  
Pages: [1] 2 »  All
  Print  
Author Topic: Mining Probability Calculation and market predictions.  (Read 16176 times)
ranger
Newbie
*
Offline Offline

Activity: 10


View Profile
February 21, 2011, 07:34:07 PM
 #1

Hi guys, I'm new here. I just started mining with HD6870 using the OpenCL miner. I'm doing about 210Mhash/sec, which according to the probability calculator (http://www.alloscomp.com/bitcoin/calculator.php) means that on average I should generate a block about every 8 days.

Instead, I have generated 3 blocks in about 4 days. This can mean two things: 1. I'm extremely lucky, or 2. the rate calculator is not quite right.

This discovery has got me thinking, if Bitcoins can be generated this quickly by just a single PC, doesn't that make the bitcoin market very unstable and likely to collapse? The more people learn about bitcoins, the more will be generated. Supply will increase, the value will go down. I'm talking about the bitcoin/USD exchange rate here, which seems rather volatile. I've read a lot of posts here on the forum by people who support bitcoin with all their heart (as do I!), who are predicting the exchange rate to soar the coming year. That seems rather impossible to me, considering how fast the coins are going to be generated from now on. I realize the system balances itself by increasing the difficulty factor, but the next devaluation is still 90000 blocks away, and who knows what that will do to the market.

Any thoughts?
1480787361
Hero Member
*
Offline Offline

Posts: 1480787361

View Profile Personal Message (Offline)

Ignore
1480787361
Reply with quote  #2

1480787361
Report to moderator
Advertised sites are not endorsed by the Bitcoin Forum. They may be unsafe, untrustworthy, or illegal in your jurisdiction. Advertise here.
1480787361
Hero Member
*
Offline Offline

Posts: 1480787361

View Profile Personal Message (Offline)

Ignore
1480787361
Reply with quote  #2

1480787361
Report to moderator
1480787361
Hero Member
*
Offline Offline

Posts: 1480787361

View Profile Personal Message (Offline)

Ignore
1480787361
Reply with quote  #2

1480787361
Report to moderator
theGECK
Sr. Member
****
Offline Offline

Activity: 410



View Profile
February 21, 2011, 07:36:08 PM
 #2

I seem to remember that the difficulty adjusts every 2016 blocks, not ever 90k+ blocks. The frequent adjustments of the difficulty should be enough to stop what you are saying could happen.

Use my referral codes for Bitcoin faucets and I'll send you 25% of my referral bonus - Win/Win! PM for details on all sites available or use one of the links here.

FreeBitco.in | FreeDoge.co.in
ribuck
Donator
Legendary
*
Offline Offline

Activity: 826


View Profile
February 21, 2011, 07:38:11 PM
 #3

You were just lucky with your generated blocks. Generations are highly variable. When you have a long dry spell without a block (which you will), just look back and remember that there were good times too.

As theGECK said, the generation difficulty factor adjusts every 2016 blocks (every couple of weeks). The adjustment in 90,000 blocks will be to the payout rate, from 50 to 25 BTC per block, which is a tapering-off so that generation of new coins will eventually stop.
ranger
Newbie
*
Offline Offline

Activity: 10


View Profile
February 21, 2011, 07:42:26 PM
 #4

Since we're on the topic, another question: how is the difficulty level managed? Is it just coded into the clients so they know to increase the difficulty level by themselves? What if a client doesn't increase their difficulty and calculates an easy block instead? Will the network reject it?

Also, I'm wondering just how lucky I was, since that's basically 3 blocks after another being generated in less than average time. If the chance of finding a block with my calculation rate in 2days were 10%, then the chance of finding 3 blocks this quickly would be less than 0.1%. Quite strange if you ask me.
Blitz­
Donator
Legendary
*
Offline Offline

Activity: 1596


"Cut Your Loose"


View Profile
February 21, 2011, 07:45:43 PM
 #5

Since we're on the topic, another question: how is the difficulty level managed? Is it just coded into the clients so they know to increase the difficulty level by themselves? What if a client doesn't increase their difficulty and calculates an easy block instead? Will the network reject it?
The difficulty is determined by the network by analyzing how long it took to generate 2016 blocks. The ideal is 14 days, so if it takes shorter than this, and it usually does, the difficulty will rise accordingly.

"Bitcoin had been transformed from an anarachistic challenge to the financial status quo, to the crypto spawn of Satan, fuelled by cut-throat greed and delusions of avarice." - MatTheCat
"these people don't seem to want to stop till Bitcoin is completely destroyed and left like an old cum rag in the corner of the room." - ShroomsKit
ribuck
Donator
Legendary
*
Offline Offline

Activity: 826


View Profile
February 21, 2011, 07:48:51 PM
 #6

the chance of finding 3 blocks this quickly would be less than 0.1%
If there are a thousand people generating, someone's likely to have a 0.1% experience. This was your turn. Don't worry, you're unlikely to find the next three so quickly.
jgarzik
Legendary
*
Offline Offline

Activity: 1470


View Profile
February 21, 2011, 07:49:27 PM
 #7

Hi guys, I'm new here. I just started mining with HD6870 using the OpenCL miner. I'm doing about 210Mhash/sec, which according to the probability calculator (http://www.alloscomp.com/bitcoin/calculator.php) means that on average I should generate a block about every 8 days.

Instead, I have generated 3 blocks in about 4 days. This can mean two things: 1. I'm extremely lucky, or 2. the rate calculator is not quite right.

You were lucky.  In 3-4 days, my 1000 Mhash/sec generated no blocks.

It's a lottery.

Over time you should see the statistical average, but right now your sample size is tiny.

Jeff Garzik, bitcoin core dev team and BitPay engineer; opinions are my own, not my employer.
Donations / tip jar: 1BrufViLKnSWtuWGkryPsKsxonV2NQ7Tcj
Raulo
Full Member
***
Offline Offline

Activity: 238


View Profile
February 21, 2011, 07:49:50 PM
 #8

Also, I'm wondering just how lucky I was, since that's basically 3 blocks after another being generated in less than average time. If the chance of finding a block with my calculation rate in 2days were 10%, then the chance of finding 3 blocks this quickly would be less than 0.1%. Quite strange if you ask me.

You were lucky but not that lucky. The probability is described by Poisson distribution. The probability of getting at least 3 blocks when only 0.5 were expected on average is 1.4%
http://stattrek.com/Tables/Poisson.aspx


1HAoJag4C3XtAmQJAhE9FTAAJWFcrvpdLM
ranger
Newbie
*
Offline Offline

Activity: 10


View Profile
February 21, 2011, 08:45:25 PM
 #9

That's pretty interesting. So I'm less lucky than I thought, and the calculation was correct. That's good news then, since it's not entirely unlikely for me to expect a similar result in the future Wink

I tried to summarize what I know about bitcoins and bitcoin mining on my blog. Would welcome some feedback: http://rheide.wordpress.com/2011/02/21/thoughts-on-bitcoin-mining/
ribuck
Donator
Legendary
*
Offline Offline

Activity: 826


View Profile
February 21, 2011, 08:51:38 PM
 #10

You wrote in the article that "eventually everyone will hit the jackpot". I think it's important not to raise people's expectations too high. Already, you need a GPU to have a reliable chance of generating blocks. And the difficulty is likely to keep rising. Many of those who are generating with a CPU will never generate a block.
ranger
Newbie
*
Offline Offline

Activity: 10


View Profile
February 21, 2011, 11:49:08 PM
 #11

You wrote in the article that "eventually everyone will hit the jackpot". I think it's important not to raise people's expectations too high. Already, you need a GPU to have a reliable chance of generating blocks. And the difficulty is likely to keep rising. Many of those who are generating with a CPU will never generate a block.

Thanks. I added a note about it.
ranger
Newbie
*
Offline Offline

Activity: 10


View Profile
February 22, 2011, 12:03:03 AM
 #12

Also, one more question. The wiki here (https://en.bitcoin.it/wiki/Target) says that 'the network' decides the next target for each round. Who is 'the network'? Am I correct in understanding that each client analyzes the past block chain and then decides for itself what the next target will be? I feel there's still a gap in my understanding between the network acknowledging what constitutes a 'winning' hash and that hash actually being converted into tangible (well..) bitcoins.

casascius
Mike Caldwell
VIP
Legendary
*
Offline Offline

Activity: 1344


The Casascius 1oz 10BTC Silver Round (w/ Gold B)


View Profile WWW
February 22, 2011, 04:58:02 AM
 #13

Also, one more question. The wiki here (https://en.bitcoin.it/wiki/Target) says that 'the network' decides the next target for each round. Who is 'the network'? Am I correct in understanding that each client analyzes the past block chain and then decides for itself what the next target will be? I feel there's still a gap in my understanding between the network acknowledging what constitutes a 'winning' hash and that hash actually being converted into tangible (well..) bitcoins.



Yes, that is exactly true, but only on certain block numbers where that is allowed - once every 2016 blocks.  If you are the miner that mines one of those blocks, your calculation of difficulty is the one that sticks.  It is saved in the block itself, and everybody uses it for the next 2016 blocks.

What converts the block into bitcoins is... each miner is constantly attempting to hash a block of all the most recent transactions, plus an acknowledgment of the latest block, plus a brand new transaction that gives 50 new btc to himself.  So every miner is trying to hash a different "version" of the most recent block...one that pays himself the reward.

Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable.  I never believe them.  If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins.  I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion.  Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice.  Don't keep coins online. Use paper wallets instead.
bitk
Newbie
*
Offline Offline

Activity: 25


View Profile
February 23, 2011, 09:12:44 PM
 #14

To me, the calculator looks off by a 10% factor or more.
It's expected value is higher of what I get on slush's pool, and since the pool is meant to get your throughput (almost) at the expected value, it's either something wrong with me and the pool, or an over optimistic calculator.
Also, I went mining for about 5 days, with an expected 3 days of payout, but I found nothing. But that sounded perfectly normal to my ears.

Bitcoin to prepaid phone credit - http://bitcointalk.org/index.php?topic=3620.0
(Italy preferred, but if you are from the rest of the world, PM me and we might find a deal!)
casascius
Mike Caldwell
VIP
Legendary
*
Offline Offline

Activity: 1344


The Casascius 1oz 10BTC Silver Round (w/ Gold B)


View Profile WWW
February 23, 2011, 09:55:26 PM
 #15

To me, the calculator looks off by a 10% factor or more.
It's expected value is higher of what I get on slush's pool, and since the pool is meant to get your throughput (almost) at the expected value, it's either something wrong with me and the pool, or an over optimistic calculator.
Also, I went mining for about 5 days, with an expected 3 days of payout, but I found nothing. But that sounded perfectly normal to my ears.

Slush keeps the 10% for himself

Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable.  I never believe them.  If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins.  I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion.  Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice.  Don't keep coins online. Use paper wallets instead.
gusti
Legendary
*
Offline Offline

Activity: 1102


View Profile
February 23, 2011, 09:57:20 PM
 #16

To me, the calculator looks off by a 10% factor or more.
It's expected value is higher of what I get on slush's pool, and since the pool is meant to get your throughput (almost) at the expected value, it's either something wrong with me and the pool, or an over optimistic calculator.
Also, I went mining for about 5 days, with an expected 3 days of payout, but I found nothing. But that sounded perfectly normal to my ears.

Slush keeps the 10% for himself

You mean he keeps more than the advised 2% ?

If you don't own the private keys, you don't own the coins.
Raulo
Full Member
***
Offline Offline

Activity: 238


View Profile
February 23, 2011, 10:05:26 PM
 #17

Slush keeps the 10% for himself

You mean he keeps more than the advised 2% ?


No, it means caucasius is not aware variability can be that high.

Slush's pool has some daily variability. Bad day for the pool, and your mining income can be 20% lower.

1HAoJag4C3XtAmQJAhE9FTAAJWFcrvpdLM
slush
Legendary
*
Offline Offline

Activity: 1358



View Profile WWW
February 23, 2011, 10:06:29 PM
 #18

It's expected value is higher of what I get on slush's pool, and since the pool is meant to get your throughput (almost) at the expected value, it's either something wrong with me and the pool, or an over optimistic calculator.
Also, I went mining for about 5 days, with an expected 3 days of payout, but I found nothing. But that sounded perfectly normal to my ears.

1) My pool keeps 2%, not 10%
2) Mining is still probabilistic, even in the pool. Even pool have bad or good days.
3) There were some outages, because keep getwork based pool up is quite difficult. This also cut the daily reward
4) I don't know your hashrate, but score based system makes pool mining more probabilistic than share based. If you have poor hashrate, you still might be more unlucky.


Nefario
Hero Member
*****
Offline Offline

Activity: 602


GLBSE Support support@glbse.com


View Profile WWW
February 24, 2011, 02:47:21 AM
 #19

the chance of finding 3 blocks this quickly would be less than 0.1%
If there are a thousand people generating, someone's likely to have a 0.1% experience. This was your turn. Don't worry, you're unlikely to find the next three so quickly.

If you play the lottery I am sure your chance of winning is much worse than 0.1% but people still win.

PGP key id at pgp.mit.edu 0xA68F4B7C

To get help and support for GLBSE please email support@glbse.com
ranger
Newbie
*
Offline Offline

Activity: 10


View Profile
February 24, 2011, 10:44:16 AM
 #20

Being confronted with not finding any coins for days, I can't help but think about reasons why I haven't found them. I keep thinking that perhaps if I restart the client more often, or restart my PC, or erase my entire Bitcoin folder and start from scratch, that I'll find as much coins as I did in the beginning.

I know that all of that does not make any sense based on the things I know about bitcoins. The system simply doesn't (shouldn't?) work that way, technically. But has anyone actually tried this? I wonder if people have their own 'good luck charms' - eg. actions that you perform that makes you think that you'll find bitcoins faster. Thoughts?
Pages: [1] 2 »  All
  Print  
 
Jump to:  

Sponsored by , a Bitcoin-accepting VPN.
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!