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1061  Economy / Services / Re: Free bitcoins: Advertise these links in your sig! on: May 09, 2013, 03:46:50 AM
I'm down with adding a ripplescam signature, but I would write it a bit more eloquently. I think their medium-term plan is to get people to transfer them real money to fund their IOUs before they disappear, not just to have a 100% premine coin. Having that message in my signature would make my plan of disposing of those scamcoins on suckers/believers harder though Tongue.
1062  Other / Beginners & Help / Re: Bit Ripple starter giveaway on: May 06, 2013, 07:53:42 AM
Hello everyone,

So I am new to Bitcointalk, haven't felt the need to register (can usually find answers to most of my questions just by searching, although now that I am registered I will likely be getting more involved) but I recently became aware of Ripple via stackexchange.
Be aware that there was a flood of Ripple questions and answers on stackexchange, posted and answered by various sock puppets of opencoin, basically using that site as advertising. Take nothing there about ripple as anyone having a real question, nor interpret an answer being an honest one.
1063  Bitcoin / Bitcoin Discussion / Re: Boycott 0.8.2 on: May 06, 2013, 12:40:28 AM
Yes cause they censored them, either conform to our standards or don't do business anymore.
You sure like that word. I thought I did too ... too bad you're well on your way to destroying its meaning.

What the heck are you talking about? How was anyone censored? Or are you just happily making up stuff? Sad
The only thing censored is by me hitting the ignore button on the OP and anybody else posting stupid stuff here. Plonk!
1064  Other / Beginners & Help / Re: Verification failed, check hardware! on: May 05, 2013, 10:05:30 AM
Yes, if you want a new driver to work, you can ask (with BTC) a miner kernel developer to rewrite the kernel you have chosen in guiminer to support whatever the newest driver and SDK has done to break OpenCL applications. This will benefit few, as dedicated miners already run the appropriate driver to give them not only working but the fastest hashing, and don't use guiminer.
1065  Bitcoin / Mining / Re: The PPNLS system. on: May 04, 2013, 10:10:35 PM
I really don't understand the PPNLS system...  Any suggestions?

Yes, read about the PPLNS system until you understand.

https://bitcointalk.org/index.php?topic=39832.5
https://bitcoil.co.il/pool_summary.pdf
1066  Bitcoin / Technical Support / Re: Can't Sync Bitcoin QT AND No Blockchain File on PC on: May 04, 2013, 06:56:14 PM
2013-05-04 11:50:03 received block 00000000000000ff4aaa342f804a2731bb9f39a784a7f1d86685b35f144cd73a
2013-05-04 11:50:03 InvalidChainFound: invalid block=00000000000000ff4aaa342f804a2731bb9f39a784a7f1d86685b35f144cd73a  height=234477  work=1131399971692442463964  date=2013-05-04 11:47:02
2013-05-04 11:50:03 InvalidChainFound:  current best=0000000000000051e75ec922ddfed09dc3ca0a72f0e8bbc875d7b3fb370d7524  height=234410  work=1128500345104905542838  date=2013-05-04 01:24:51

This is the crux of the problem, your local blockchain database is corrupted and the client can't build on that. It doesn't have the intelligence to try to get the block 234410 again from the network and replace your screwed up version with the correct one.

You will need to delete the blocks and chainstate directories from your bitcoin data directory and attempt to resync the blockchain from the start. Typically this kind of random corruption indicates bad hardware, such as a bad sector on a hard drive or bad math from an overheating or overclocked CPU.
1067  Other / CPU/GPU Bitcoin mining hardware / Re: How many video cards can cool 3-4 Kilowatt air conditioner? on: May 04, 2013, 06:43:33 PM
The amount of heat generated by 1 kilowatt worth of computer (about four 200W video cards + system + 900W power supply inefficiency):

1kWh = 3,412 BTU

So we need 3400 BTU of A/C to remove that much heat generation.

The the next question is how much power will that cooling require. We must look at the the energy efficiency of air conditioning, which is typically given as SEER (seasonal energy efficiency ratio), which we must translate into an actual efficiency measure.

COP = 3.41214/EER

As a low-water benchmark, lets look at a 5000 BTU window AC unit ($110 on lowes.com website)
Specs: EER=9.7, Watts=515 (calculated efficiency multiplier: 2.84)

So this particular model moves 1462W of heat with 515W. A central AC will be more efficient, so 3000kW * 2.84+ = at least 8000 watts (but nothing left to actually cool your house against summer temperatures).

Real miners don't use AC though, why reduce profitability? Put the units in a closed room with a window fan, or in the garage.
1068  Other / Beginners & Help / Re: Still a little confused on Wallets. on: May 04, 2013, 05:10:36 AM
Bitcoin gives you all you can eat addresses for free! Just put keypool=10000 in your bitcoin.conf file, now your wallet has 10,000 pregenerated addresses in it (you'll have a backup that never becomes obsolete).

There are 1461501637330902918203684832716283019655932542976 possible addresses. That's enough for 100x the world's current population to have 1826877046663628647754606040895353774 addresses each.

There will be a maximum of 2100000000000000 Bitcoin base units (a satoshi, or 0.00000001 bitcoin).
Even if every single base unit that will ever be created were put in a different address, there will still be 1461501637330902918203684832716280919655932542976 empty addresses. The chance of you generating an address that has a satoshi in it will be 1 in 695953160633763294382707063198230.

So in other words, it doesn't matter if you create lots of addresses and delete them. If you never use them, the network doesn't even know they exist.

1069  Other / Beginners & Help / Re: How faucets make money? on: May 04, 2013, 02:10:51 AM
Most "faucets" are a scam to get you to click on ads and pay you nothing but unspendable dust. They are pale imitations of the original Bitcoin faucet.

I've personally put about 10000 coins in this faucet, and it still gives out coins, no strings attached: http://tpfaucet.appspot.com/
1070  Other / Meta / Re: BOOKMARK THIS SITE AS https://109.201.133.65, DOMAIN WAS TRANSFERRED on: May 03, 2013, 10:38:58 AM
Domains get hacked often. The problem is if someone hacked the domain registrar account and transferred the domain away, it may be a bit of work to get it back. It's 7pm on a Friday in Japan, 3am in the US. It will take time through the Transfer Dispute Resolution Protocol if the receiving domain registrar doesn't immediately hand it back on the word of registrar #1.
1071  Other / Meta / Re: DNS DOWN !!!! on: May 03, 2013, 10:31:29 AM
better use namecoin

http://explorer.dot-bit.org/n/45362

the namecoin bitcointalk.bit domain points to the wrong IP address, it was bitcointalk.org in mid 2012 https://dazzlepod.com/ip/50.97.137.52/

Whoever created that needs to not forget about updating it.
1072  Other / Meta / BOOKMARK THIS SITE AS https://109.201.133.65, if domain disappears again, etc. on: May 03, 2013, 10:10:28 AM
100 users and dropping, so note this IP, the DNS record was changed for bitcointalk.org away from the forum.

EDIT: site got it's domain back, no need to worry now.
1073  Alternate cryptocurrencies / Altcoin Discussion / Re: Confirmations required for trustable transactions. on: May 03, 2013, 06:42:28 AM
You are wrong. The truth is not a myth. The higher hashrate of Bitcoin does allow it to fend off a particular attacker better than other alt-coins would fare, but then you go into falsehoods.

https://bitcointalk.org/index.php?topic=177308.msg1853377#msg1853377

If you need help, please read the satoshi paper until you understand it. If you can't understand the statistics, you shouldn't foray into starting topics where you claim to answer some question nobody was asking about.
1074  Economy / Trading Discussion / Re: SierraChart bridge - Realtime Bitcoin charts [v0.5] (MtGox, Intersango, ...) on: May 03, 2013, 05:03:35 AM

SCID full history files:
from first trade 07/17/2010 23:09:17, to 04/30/2013 23:59:59 (UTC, tick accurate, precision 2):
(extract to C:\SierraChart\data\ before starting SierraChart)

http://we.lovebitco.in/schart/mtgoxUSD.scid.UTC.7z (18.2MB/182MB)
http://we.lovebitco.in/schart/otherALL.scid.UTC.7z (8.2MB/86.4MB)
Sorry, I forgot to actually upload the "other history" file, it's up now and includes other exchanges and currencies. Funny how nobody dropped me the 411 on the 404.
1075  Economy / Service Discussion / Re: CoinLab suing MtGox for $75 milliion? on: May 03, 2013, 03:01:19 AM
MtGox: we determined it was a bad idea to go through with giving this shady looking individual the banking credentials and passwords of non-consenting users, especially since he got into the scamcoin business.

Me: Hey coinlab, where can I serve you notice? Me and 1000 others will get default judgements against your "company" in every state of the union, even before your lawsuit with MtGox is dismissed in summary judgement.
1076  Bitcoin / Development & Technical Discussion / Re: 234078 Longest block to solve yet? on: May 03, 2013, 02:20:43 AM
It's not a bell curve, the probability density function of an exponential distribution looks like this:



Note that the average block time is 10 minutes (1/λ), but 50% of the blocks are less than 6.93 minutes (the median ln(2)/λ).

The reason that it makes no difference is: whether the geometric distribution (which counts individual hashes) is calculated for difficulty 1 or difficulty 10000000, the probability of a quantile (such as calculating the probability of a block taking 100 minutes) is the same within several decimal points. In fact it is already identical to the exponential (continuous) function with three digits by difficulty 1, higher difficulty just makes the density function of geometric converge to exponential with even more digits of identity.

http://math.stackexchange.com/questions/93098/how-does-a-geometric-distribution-converge-to-an-exponential-distribution

Here's a monte carlo simulation of a geometric distribution density, the red line is exponential:

See how much like the exponential it is? This example shows a 0.1 probability; Bitcoin's current probability is 0.0000000000000000231. With a lower probability,the steps disappear and the distribution converges to exponential.

So the answer is: the probability of a block taking 62 minutes (given a constant hashrate equivalent to difficulty) is 0.2029%, whether the difficulty is 1 or a billion.
1077  Bitcoin / Development & Technical Discussion / Re: 234078 Longest block to solve yet? on: May 02, 2013, 09:39:25 PM
My stats are a little rusty, but as far as I see, it doesn't, it goes up.

Hashing is Bernoulli trial, either you beat the target or you don't. That gives mining a geometric distribution, and so the variance (in number of hashes required) is (1-p)/p2. The re-targeting algorithm tries to keep the hashrate directly proportional to 1/p, so the variance in time quadratically increases with the hashrate. Right?

I guess the phenomenon above was a much higher variance in hashrate because of people turning their computers off at night, whereas now the variance is greatly reduced due to increased numbers and because miners tend to keep the gear running 24/7.

Only 'technically', on a very small scale, is the variance different. In reality it is unobservable at different difficulties.

Hashing is typically modeled as an exponential distribution, a continuous series, however it is actually a geometric distribution. The probability is so low though, that the R statistics package fails to compute due to overflow errors with statistics on much more than difficulty 1.

The variance is given for a geometric distribution as:



You can see that for extremely small p (probability of one hash finding a block), the top numerator approaches 1, becoming insignificant compared to the p2.

The high block times around 20000-30000 has something to do with the satoshi miner and others not making much hashes during that time, there was much less than difficulty 1 worth of mining being done. I could eliminate the first year of Bitcoin to get a better list of long blocks, long due to variance rather than low hashrate.
1078  Bitcoin / Development & Technical Discussion / Re: DNS and wallet addresses on: May 02, 2013, 02:22:05 AM
much harder to forge:

http://explorer.dot-bit.org/n/74491
1079  Bitcoin / Development & Technical Discussion / Re: why not measure difficulty in bits? on: May 02, 2013, 01:39:04 AM
The difficulty is actually in bits, the field in the block that contains it is called bits, which is decoded into the target.

Here's the current target, a hash has to be smaller than this number:
00000000000001AA3D0000000000000000000000000000000000000000000000

or in binary:
0000000000000000000000000000000000000000000000000000000110101010001111010000000 0000000000000000000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000000000000000000 0000000000000000000

The difficulty is easy to comprehend and is what is presented to users. What you are proposing is harder:

>>> math.log(2**256/int('00000000000001AA3D0000000000000000000000000000000000000000000000',16),2)
55.26448364017038

What  "bit" difficulty would be 10% harder?

>>> math.log(2**256/((int('00000000000001AA3D0000000000000000000000000000000000000000000000',16))/1.10),2)
55.40198716392032

Satoshi got it right. Not everyone uses Python as their calculator. Use a base difficulty, where 1 = 1 block find per ~4295032833.0 hashes on average, and higher difficulties are multipliers of that.
1080  Bitcoin / Development & Technical Discussion / Re: 234078 Longest block to solve yet? on: May 02, 2013, 12:36:21 AM
Most long blocks came early in Bitcoin, here's 212 blocks (over 100 minutes since last block timestamp)

Note that the block timestamp is based on the mining computer's time, there are more blocks than this with a negative time.

15324 1508.9  
16564 1506.5  
15     1452.6  
16592 1229.7  
20189 1003.4  
19724 785.5    
21438 637.0    
19722 625.6    
28     514.7    
16490 511.4    
20432 507.1    
20364 500.2    
20349 488.8    
21389 468.7    
19565 433.3    
15048 422.9    
19726 415.1    
74638 411.3    
21446 392.9    
21527 384.7    
21466 384.2    
16468 380.7    
26242 368.3    
21359 357.8    
21449 342.3    
21463 330.1    
21382 327.1    
21376 321.3    
21383 308.6    
23418 305.4    
21585 302.0    
23434 300.7    
20384 299.6    
16215 294.8    
15424 285.1    
23433 277.6    
21442 263.8    
16286 263.8    
21464 261.6    
22945 260.1    
22527 259.3    
20325 248.2    
21458 238.0    
21374 234.9    
19725 234.2    
21418 232.2    
21444 230.8    
28705 226.3    
21440 225.9    
21348 225.1    
1390   224.3    
11964 223.8    
169   222.4    
21462 220.2    
21403 217.6    
21331 217.3    
20435 216.1    
8231   214.7    
20439 211.4    
1398   211.2    
32647 208.9    
13889 208.9    
20190 205.3    
16271 202.3    
20187 198.4    
21361 196.8    
13898 196.4    
1917   196.1    
21340 195.0    
25788 194.1    
26237 191.6    
20405 190.9    
8211   190.7    
20357 190.7    
1296   188.3    
21385 188.2    
11966 186.9    
32629 186.3    
15228 186.1    
21393 179.2    
21459 178.8    
20344 175.6    
8226   175.2    
20008 174.9    
163   174.2    
21428 172.7    
20361 170.8    
20343 170.4    
18030 166.6    
79     165.9    
20339 163.7    
23425 163.0    
21380 162.4    
20436 161.9    
21584 161.5    
20418 160.8    
21345 160.1    
25740 158.1    
20417 157.4    
20351 157.3    
21581 156.5    
21443 155.1    
1916   155.1    
20308 155.0    
28742 154.3    
16588 154.0    
21447 150.8    
20427 150.4    
23426 148.7    
22950 147.5    
13082 146.9    
21441 146.5    
21332 146.5    
15331 146.3    
20390 145.0    
155290 144.8    
1389   143.5    
149098 141.0    
20310 140.0    
20356 137.2    
70718 135.9    
21423 134.5    
70665 133.2    
20304 132.8    
15818 132.8    
21369 132.2    
20333 132.0    
20376 129.3    
20188 128.7    
17149 127.9    
21325 127.5    
20438 126.2    
20421 124.4    
22018 123.0    
32527 122.1    
25132 122.0    
15222 121.8    
69515 121.4    
20203 121.3    
76594 121.2    
26275 121.0    
20191 120.9    
26236 120.6    
105909 120.5    
25889 120.3    
28702 120.2    
23421 120.1    
156113 119.6    
154185 119.4    
19951 117.8    
20411 116.4    
21586 116.2    
21360 115.9    
16590 115.6    
24419 115.4    
16565 115.3    
20359 115.3    
26843 114.6    
24956 114.4    
163966 114.0    
21323 113.4    
26873 113.2    
24415 112.8    
24494 112.7    
21422 112.5    
23430 112.3    
207497 112.2    
26249 112.1    
26201 112.0    
26190 111.6    
87107 111.2    
175720 110.5    
26212 110.1    
20327 109.6    
21451 109.5    
18253 109.4    
28731 108.2    
21334 108.0    
26104 107.5    
8223   107.0    
205771 106.5    
22158 106.3    
21461 106.2    
32632 105.9    
13892 105.7    
21433 105.7    
25130 105.5    
206669 105.4    
28697 105.3    
152996 104.7    
204798 104.4    
20347 104.3    
18265 104.3    
25033 104.3    
20334 104.2    
20381 103.8    
21408 103.5    
28771 103.5    
8227   103.1    
26260 102.9    
21597 102.3    
154346 102.2    
28749 102.1    
19977 102.0    
25117 101.9    
24263 101.8    
21373 101.5    
26126 101.3    
15230 101.0    
25147 100.2    
26251 100.1  
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