FreeBitco.in-$200 FreeBTC🏎Win Lambo🔥0.2BTC DailyJackpot🏆$32,500 Wager Contest - page 428.

wetsuit

legendary

Activity: 981

Merit: 1026

Quote from: natri on June 20, 2014, 02:36:44 PM

Quote from: Luror on June 20, 2014, 02:12:02 PM

But you said you made only 500 rolls? Or did you mean some bigger test? You need more rolls to get 3rd and 4th prizes (at least 1250-5000).

That last statement ("I've never rolled more than 9993 on any of my multiplier or regular rolls on neither faucet") I referred to all of my plays on either freebitco.in and freedoge.co.in which total way over 2000 rolls so by calculating 1-(9993/10000)^2000+ the probability should be 75%+.

Ok, lets assume prob for rolling 10k is 1/20000. But by simply checking the freebitco.in WEBSITE STATS, there was currently 538,271,966 played and 394.52490422 BTC earned, if we consider that you can ONLY win top roll price (huge undervaluation) and probability is 1/20000 to earn ONLY 0.1 BTC (undervalued) -> the expected earned value of BTC should be 2700 BTC (way more than 394).

And if we say that all ppl were extremely unlucky we can check;
variance=npq=538271996*1/20000*19999/20000
sqrt(var)=164

99.7% rule (3 std deviations): Still users should earn at LEAST: 2700-3*164= 2200 BTC, and this is with only top win of 0.1 btc.

Those rolls include both free and multiply rolls, and multiply rolls are way more in number.

Luror

full member

Activity: 215

Merit: 100

Quote from: wetsuit on June 20, 2014, 02:16:38 PM

Quote from: Luror on June 20, 2014, 02:12:02 PM

Quote from: natri on June 20, 2014, 12:00:44 PM

Anyways, I've actually tested the randomness of rolls and the result was that rolls ARE NOT RANDOM, p=0,004 (sample 500, chi-squared).
This low p means it's almost impossible that I made error of type I, so rolls actually aren't random at all...
More info regarding my testing procedure here: http://www.reddit.com/r/Bitcoin/comments/28dtaa/wondering_freebitcoin_provably_unfair/

This is interesting, it is possible after all that pseudo-random numbers (for seeds) are not quite random. Why didn't you share full test results? It would be nice for someone to repeat it (though it's quite time consuming: 500 hours).

Quote from: natri on June 20, 2014, 12:00:44 PM

(btw, I've never rolled more than 9993 on any of my multiplier or regular rolls on neither faucet, probability of which should be over 75%...)

But you said you made only 500 rolls? Or did you mean some bigger test? You need more rolls to get 3rd and 4th prizes (at least 1250-5000).

Quote from: Luror on March 31, 2014, 10:13:56 AM

[0 - 9885]: ~ 1/20000 + 9885/10000 = 0.98855
[9886 - 9985] ~ (9985-9886+1)/10000 = 0.01 (~ once per 100 rolls)
[9986 - 9993] ~ (9993-9986+1)/10000 = 0.0008 (~ once per 1250 rolls)
[9994 - 9997] ~ (9997-9994+1)/10000 = 0.0004 (~ once per 2500 rolls)
[9998 - 9999] ~ (9999-9998+1)/10000 = 0.0002 (~ once per 5000 rolls)
[10000] ~ 1/20000 = 0.00005 (~ once per 20 000 rolls)

sanity check: 0.98855+0.01+0.0008+0.0004+0.0002+0.00005 = 1

The client seeds are actually generated using javascript entirely on the client side. This is the part of the Javascript code that generates the client seed (can be found in the JS file http://static4.freebitco.in/min/main1403284658.js now but the name of the file changes when I make updates) :

Code:

charSet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
var randomString = '';
for (var i = 0; i < 16; i++)
{
var randomPoz = Math.floor(Math.random() * charSet.length);
randomString += charSet.substring(randomPoz,randomPoz+1);
}
$('#next_client_seed').val(randomString);

Ok, I don't know much about Javascript programming, but I googled a little, and it seems Math.random() is not so good for some things, still it is unclear whether it can give effects like natri got:

https://stackoverflow.com/questions/5651789/is-math-random-cryptographically-secure
https://stackoverflow.com/questions/578700/how-trustworthy-is-javascripts-random-implementation-in-various-browsers
https://security.stackexchange.com/questions/20029/generate-cryptographically-strong-pseudorandom-numbers-in-javascript

The best answer seems to be this: http://stackoverflow.com/a/18507748

"Recent browsers expose window.crypto.getRandomValues() which is cryptographically strong" <--- can you use this?

natri

newbie

Activity: 7

Merit: 0

Quote from: Luror on June 20, 2014, 02:12:02 PM

But you said you made only 500 rolls? Or did you mean some bigger test? You need more rolls to get 3rd and 4th prizes (at least 1250-5000).

That last statement ("I've never rolled more than 9993 on any of my multiplier or regular rolls on neither faucet") I referred to all of my plays on either freebitco.in and freedoge.co.in which total way over 2000 rolls so by calculating 1-(9993/10000)^2000+ the probability should be 75%+.

Ok, lets assume prob for rolling 10k is 1/20000. But by simply checking the freebitco.in WEBSITE STATS, there was currently 538,271,966 played and 394.52490422 BTC earned, if we consider that you can ONLY win top roll price (huge undervaluation) and probability is 1/20000 to earn ONLY 0.1 BTC (undervalued) -> the expected earned value of BTC should be 2700 BTC (way more than 394).

And if we say that all ppl were extremely unlucky we can check;
variance=npq=538271996*1/20000*19999/20000
sqrt(var)=164

99.7% rule (3 std deviations): Still users should earn at LEAST: 2700-3*164= 2200 BTC, and this is with only top win of 0.1 btc.

wetsuit

legendary

Activity: 981

Merit: 1026

Quote from: Luror on June 20, 2014, 02:12:02 PM

Quote from: natri on June 20, 2014, 12:00:44 PM

Anyways, I've actually tested the randomness of rolls and the result was that rolls ARE NOT RANDOM, p=0,004 (sample 500, chi-squared).
This low p means it's almost impossible that I made error of type I, so rolls actually aren't random at all...
More info regarding my testing procedure here: http://www.reddit.com/r/Bitcoin/comments/28dtaa/wondering_freebitcoin_provably_unfair/

This is interesting, it is possible after all that pseudo-random numbers (for seeds) are not quite random. Why didn't you share full test results? It would be nice for someone to repeat it (though it's quite time consuming: 500 hours).

Quote from: natri on June 20, 2014, 12:00:44 PM

(btw, I've never rolled more than 9993 on any of my multiplier or regular rolls on neither faucet, probability of which should be over 75%...)

But you said you made only 500 rolls? Or did you mean some bigger test? You need more rolls to get 3rd and 4th prizes (at least 1250-5000).

Quote from: Luror on March 31, 2014, 10:13:56 AM

[0 - 9885]: ~ 1/20000 + 9885/10000 = 0.98855
[9886 - 9985] ~ (9985-9886+1)/10000 = 0.01 (~ once per 100 rolls)
[9986 - 9993] ~ (9993-9986+1)/10000 = 0.0008 (~ once per 1250 rolls)
[9994 - 9997] ~ (9997-9994+1)/10000 = 0.0004 (~ once per 2500 rolls)
[9998 - 9999] ~ (9999-9998+1)/10000 = 0.0002 (~ once per 5000 rolls)
[10000] ~ 1/20000 = 0.00005 (~ once per 20 000 rolls)

sanity check: 0.98855+0.01+0.0008+0.0004+0.0002+0.00005 = 1

The client seeds are actually generated using javascript entirely on the client side. This is the part of the Javascript code that generates the client seed (can be found in the JS file http://static4.freebitco.in/min/main1403284658.js now but the name of the file changes when I make updates) :

Code:

charSet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
var randomString = '';
for (var i = 0; i < 16; i++)
{
var randomPoz = Math.floor(Math.random() * charSet.length);
randomString += charSet.substring(randomPoz,randomPoz+1);
}
$('#next_client_seed').val(randomString);

Luror

full member

Activity: 215

Merit: 100

Quote from: natri on June 20, 2014, 12:00:44 PM

Anyways, I've actually tested the randomness of rolls and the result was that rolls ARE NOT RANDOM, p=0,004 (sample 500, chi-squared).
This low p means it's almost impossible that I made error of type I, so rolls actually aren't random at all...
More info regarding my testing procedure here: http://www.reddit.com/r/Bitcoin/comments/28dtaa/wondering_freebitcoin_provably_unfair/

This is interesting, it is possible after all that pseudo-random numbers (for seeds) are not quite random. Why didn't you share full test results? It would be nice for someone to repeat it (though it's quite time consuming: 500 hours).

Quote from: natri on June 20, 2014, 12:00:44 PM

(btw, I've never rolled more than 9993 on any of my multiplier or regular rolls on neither faucet, probability of which should be over 75%...)

But you said you made only 500 rolls? Or did you mean some bigger test? You need more rolls to get 3rd and 4th prizes (at least 1250-5000).

Quote from: Luror on March 31, 2014, 10:13:56 AM

[0 - 9885]: ~ 1/20000 + 9885/10000 = 0.98855
[9886 - 9985] ~ (9985-9886+1)/10000 = 0.01 (~ once per 100 rolls)
[9986 - 9993] ~ (9993-9986+1)/10000 = 0.0008 (~ once per 1250 rolls)
[9994 - 9997] ~ (9997-9994+1)/10000 = 0.0004 (~ once per 2500 rolls)
[9998 - 9999] ~ (9999-9998+1)/10000 = 0.0002 (~ once per 5000 rolls)
[10000] ~ 1/20000 = 0.00005 (~ once per 20 000 rolls)

sanity check: 0.98855+0.01+0.0008+0.0004+0.0002+0.00005 = 1

wetsuit

legendary

Activity: 981

Merit: 1026

I shall set up a javascript based roll verifier within a couple of days to hopefully stop all the "your game is not fair" accusations.

Luror

full member

Activity: 215

Merit: 100

Quote from: natri on June 20, 2014, 12:00:44 PM

Hey guys. I love this faucet however I think it is deceiving in terms of payoff and it's probability of high winnings.
Rolling a number between 1-10000 would imply a 1/10000 probability of hitting 10000, however, I think it is much lower.

The probability is actually 1/20000, take a look at my earlier post:

Quote from: Luror on March 03, 2014, 10:27:06 AM

Quote from: ingrownpocket on March 02, 2014, 05:31:48 PM

With 2889 referrals, I find it odd that I've never gotten a 50% commission from a 0.22500000 BTC payout (10000 lucky number).

I'm in doubts the probability of rolling "10000" is 0.0001 with current algorithm, it would be interesting if someone would do an independent test (run an implementation of current algorithm 1,000,000 times, look at the amount of 10000's).

upd Ok, I looked at algorithm closer, and if everything is properly randomized, we can calculate the probability theoretically:

"3. The first 8 characters of the hex string are taken and converted to a decimal.
4. This decimal is then divided by 429496.7295 and rounded up to the nearest whole number.
5. This whole number is used as your roll, with the maximum possible value being 10,000."

We have hex strings from "00000000" to "ffffffff" (0 to 4294967295), 4294967296 in total. "ffffffff" converts to 4294967295/429496.7295 = 10000.

The biggest number which will be rounded to 10000 is 9999.5, back converting it (*429496.7295), we'll get 4294752546.63525.

So the numbers from the interval [4294752547, 4294967295] will be converted to "10000", the quantity of them = 4294967295-4294752547+1 = 214749.

The probability of getting "10000" = 214749/4294967296 = 0.00005000014789402484893798828125 (~ 1/20000)

P.S. After 40,000 rolls one should get 86% probability of rolling "10000" at least once

(proof: https://www.wolframalpha.com/input/?i=1-%281-0.00005000014789402484893798828125%29^40000)

natri

newbie

Activity: 7

Merit: 0

Hey guys. I love this faucet however I think it is deceiving in terms of payoff and it's probability of high winnings.
Rolling a number between 1-10000 would imply a 1/10000 probability of hitting 10000, however, I think it is much lower.

Anyways, I've actually tested the randomness of rolls and the result was that rolls ARE NOT RANDOM, p=0,004 (sample 500, chi-squared).
This low p means it's almost impossible that I made error of type I, so rolls actually aren't random at all...
More info regarding my testing procedure here: http://www.reddit.com/r/Bitcoin/comments/28dtaa/wondering_freebitcoin_provably_unfair/

So, I would love if the rolls were truly random, even if it meant a lower top prices. Right now, it just seems deceiving to the point of scamming...
(btw, I've never rolled more than 9993 on any of my multiplier or regular rolls on neither faucet, probability of which should be over 75%...)

Raising false hopes, huh?

deisik

legendary

Activity: 3514

Merit: 1280

English ⬄ Russian Translation Services

Quote from: Mayuyu48 on June 20, 2014, 03:11:16 AM

anyone knows how much freebitco pay us for 1 roll in $?
it seems they pay us in USD instead BTC, since their payment always change when bitcoin prices change

Why does it interest you? Evidently, wetsuit buys bitcoins for dollars, that's why the payment keeps constantly changing... Roll Eyes

Mayuyu48

hero member

Activity: 644

Merit: 500

anyone knows how much freebitco pay us for 1 roll in $?
it seems they pay us in USD instead BTC, since their payment always change when bitcoin prices change

deisik

legendary

Activity: 3514

Merit: 1280

English ⬄ Russian Translation Services

Quote from: boumalo on June 20, 2014, 02:37:01 AM

Quote from: deisik on June 19, 2014, 02:03:17 PM

Quote from: energa on June 19, 2014, 01:24:27 PM

Hello

how it works?

its like gambling? or some HYIP offer?

You can gamble (like in an online casino), but you can also earn free bitcoins once an hour (free faucet). Surely not HYIP or anything related... Cool

You cannot deposit to gamble though, you can only gamble what you won from the faucets or referrals

Yeah, people would lose a lot more! Grin

boumalo

legendary

Activity: 1918

Merit: 1018

Quote from: deisik on June 19, 2014, 02:03:17 PM

Quote from: energa on June 19, 2014, 01:24:27 PM

Hello

how it works?

its like gambling? or some HYIP offer?

You can gamble (like in an online casino), but you can also earn free bitcoins once an hour (free faucet). Surely not HYIP or anything related... Cool

You cannot deposit to gamble though, you can only gamble what you won from the faucets or referrals

deisik

legendary

Activity: 3514

Merit: 1280

English ⬄ Russian Translation Services

Quote from: energa on June 19, 2014, 01:24:27 PM

Hello

how it works?

its like gambling? or some HYIP offer?

You can gamble (like in an online casino), but you can also earn free bitcoins once an hour (free faucet). Surely not HYIP or anything related... Cool

energa

newbie

Activity: 10

Merit: 0

Hello

how it works?

its like gambling? or some HYIP offer?

boumalo

legendary

Activity: 1918

Merit: 1018

Quote from: wetsuit on June 18, 2014, 07:10:21 AM

Quote from: snarlpill on June 17, 2014, 03:58:56 PM

I asked wetsuit before on here, months ago, if anybody had ever hit 10,000 in Free Roll or 8888 in the multiplier. I don't think he ever responded, but I would still be interested to know. I like low-chance wins, like when you see somebody on just-dice hitting under 5 at 5% chance and winning big.

Honestly, I do not know how many have hit the big number because I do not keep a record of rolls to keep the database load low. At 500 million rolls, keeping record of each would increase overhead by a lot.

@snarlpill : you can check the biggest jackpot@overall winners on http://freebitco.in/?op=stats

wetsuit

legendary

Activity: 981

Merit: 1026

Quote from: snarlpill on June 17, 2014, 03:58:56 PM

I asked wetsuit before on here, months ago, if anybody had ever hit 10,000 in Free Roll or 8888 in the multiplier. I don't think he ever responded, but I would still be interested to know. I like low-chance wins, like when you see somebody on just-dice hitting under 5 at 5% chance and winning big.

Honestly, I do not know how many have hit the big number because I do not keep a record of rolls to keep the database load low. At 500 million rolls, keeping record of each would increase overhead by a lot.

snarlpill

hero member

Activity: 910

Merit: 530

$5 24k Gold FREE 4 sign-up! Mene.com/invite/h5ZRRP

I asked wetsuit before on here, months ago, if anybody had ever hit 10,000 in Free Roll or 8888 in the multiplier. I don't think he ever responded, but I would still be interested to know. I like low-chance wins, like when you see somebody on just-dice hitting under 5 at 5% chance and winning big.

boumalo

legendary

Activity: 1918

Merit: 1018

Quote from: GigaBit on June 17, 2014, 11:10:26 AM

Great Site - Saved my record

http://screencast.com/t/h3p73pTh

Best site for new users to get into owning some Bitcoin.

Pays on time every time.

Congrats, keep playing Grin

I'd like someone to post a 400k 4M or 40M win

GigaBit

hero member

Activity: 1792

Merit: 514

Leading Crypto Sports Betting & Casino Platform

Great Site - Saved my record

http://screencast.com/t/h3p73pTh

Best site for new users to get into owning some Bitcoin.

Pays on time every time.

saif92

sr. member

Activity: 392

Merit: 250

Quote from: wetsuit on June 17, 2014, 10:43:24 AM

Quote from: saif92 on June 17, 2014, 10:39:35 AM

Today I received my first withdraw of 500 Doges and I love this withdraw system as you want you can withdraw I want to say please do this in bitcoin faucet also thanks

Cannot do this with bitcoin at the moment due to the high transaction fees (10,000 satoshis per withdrawal).

I am working on a way to implement this in freebitco.in where payments requests will be grouped together in a batch and users will only need to pay a tx fee of ~350 satoshi.

Oh then its ok thanks for very quick and good reply and special thanks for these 2 great faucets Grin

Topic: FreeBitco.in-$200 FreeBTC🏎Win Lambo🔥0.2BTC DailyJackpot🏆$32,500 Wager Contest - page 428. (Read 408453 times)