Bitcoin Forum

Economy => Marketplace => Topic started by: dacoinminster on May 26, 2011, 02:58:10 PM



Title: [FINISHED] Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 02:58:10 PM
Since there is no bitcoin futures market, I'm starting one. Speculate now on the value of bitcoins on 7/1/2011.

This is an experiment, so please don't bet your life savings.

Rules:

1) All bets will be tracked at this newly created address in a currently-empty wallet: http://blockexplorer.com/address/1945qfobZxdnmVJ6qBd4FgcVcWBhDXKiTV (http://blockexplorer.com/address/1945qfobZxdnmVJ6qBd4FgcVcWBhDXKiTV)
2) The "bitcents" represent your bet on the USD price of bitcoins on July 1, 2011 at noon U.S. pacific time. Examples:
      a) A bet of 1.13 BTC sent to that address is a bet of 1.13 BTC that bitcoins will be worth $13 USD on July 1st
      b) A bet of 12.08 sent to that address is a bet of 12.08 BTC that bitcoins will be worth $8 USD on July 1st
      c) A bet of 0.15 sent to that address is a bet of 0.15 BTC that bitcoins will be worth $15 on July 1st
      d) You can use sub-cents if you want. A bet of 0.015 BTC is placed on $1.50 per bitcoin
3) Winnings will be put in one pot and distributed as follows:
      a) 98% of the pot will go to the winners (those within + or - $0.50 of the final value, inclusive)
      b) 2% of the pot will go to me
      c) The pot will be split among winners by the size of their bet multiplied by the number of days in advance they made their bet (days will be fractional with resolution in seconds, per block explorer timestamps)
      d) Winnings will be returned to the sending address, so use the real bitcoin client, not a managed wallet
4) The reference price on July 1st will be determined by me, using my browser on MtGox, at exactly noon PST pacific time. If for some reason I am unable to do this, I will rely on MtGox records and/or forum members posting the price in this thread. I will do my best to be fair, and I will not be betting any of my own bitcoins, so I should be impartial.
      e) I will post the final price and who I think the winners are and how much they should get here for community vetting. I will allow for comments to accumulate over the following weekend, and then pay out on Monday Tuesday following the holiday weekend if there is no great scandal.
5) If an excessive amount of bitcoins are bet, I will probably seek a trusted forum member to hold some of the bitcoins so they aren't all in my care. My first choice would be _mndrix, followed by GavinAnderson. I would consider other highly trusted members if neither of them want to do it. Edit: See bond info below
6) New: As an incentive to kick things off, I'm offering 0.1BTC each to the first 5 betters: http://forum.bitcoin.org/index.php?topic=10008.msg144375#msg144375

Obviously placing multiple bets at different prices is going to be a common strategy.


Update: Michael Hendrix (of Coinpal/Coincard fame) has agreed to hold 50 of my personal bitcoins as a bond against any mishaps with the money. You can see where he posted in the thread below with his PGP signature agreeing to hold my bond (http://forum.bitcoin.org/index.php?topic=10008.msg144414#msg144414). You can view the bond here: http://blockexplorer.com/address/168bokgyuxUYp1HL7xeyZzQCj7dEKZQyuR

For posterity, here is the email I sent him:


Quote
---------- Forwarded message ----------
From: *********************
Date: Thu, May 26, 2011 at 12:09 PM
Subject: Bitcoin Bond
To: m*chael@ndrix.org, serv*ce@ndrix.org


Hey Michael,

Would you be willing to hold a 50BTC bond for me? I'm running an experiment on the bitcoin forum with bitcoin futures, and I need to have somebody trustworthy to hold some bitcoins for me in case I make off with all the money.

The thread is here: http://forum.bitcoin.org/index.php?topic=10008.0

If you are willing to hold the bitcoins, please reply to me by email AND post on the thread (so I know your new forum name is really you) with an address to send the bitcoins to. Then I can post bond with you.

If people bet more than 50 bitcoins, I'll probably send you additional bitcoins for safekeeping at the same address.

Please let me know whether you are willing.

Thanks!

-********* (dacoinminster)


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: bitcoinfrenzy on May 26, 2011, 04:34:42 PM
Interesting concept, although I think there's a fundamental flaw in that the payout is in BTC.  This rewards long bets more than short bets, and would probably make it unprofitable to bet on a severe decline in BTC, even if you thought one was likely to happen.  You can see an example of the problem at http://www.bitcoinfrenzy.com/2011/05/problems-with-proposed-bitcoin-futures.html (http://www.bitcoinfrenzy.com/2011/05/problems-with-proposed-bitcoin-futures.html).


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 06:54:22 PM
Interesting concept, although I think there's a fundamental flaw in that the payout is in BTC.  This rewards long bets more than short bets, and would probably make it unprofitable to bet on a severe decline in BTC, even if you thought one was likely to happen.  You can see an example of the problem at http://www.bitcoinfrenzy.com/2011/05/problems-with-proposed-bitcoin-futures.html (http://www.bitcoinfrenzy.com/2011/05/problems-with-proposed-bitcoin-futures.html).

Very good point. This is NOT a good way to hedge against a bitcoin collapse (such a hedge would have to be denominated in a currency other than bitcoins, by definition). Betting on anything from a 50% drop to a big gain, however, should be quite profitable if you are right.

Of course nobody has placed any bets yet. I'm looking into posting a bond of my personal bitcoins with someone to prove my honesty.

Update: See the first post in this thread for current bond information.



Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: bitcoinfrenzy on May 26, 2011, 07:03:45 PM
Can you explain how the following would work with an example? 

Quote
The pot will be split among winners by the size of their bet multiplied by the number of days in advance they made their bet (days will be fractional with resolution in seconds, per block explorer timestamps)

Thanks.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 07:15:29 PM
Can you explain how the following would work with an example? 

Quote
The pot will be split among winners by the size of their bet multiplied by the number of days in advance they made their bet (days will be fractional with resolution in seconds, per block explorer timestamps)

Thanks.

Sure. Obviously the closer we get to July 1st, the more confident someone can be about a bet they place. If I had no time component, all the bets would come in at the end.

Consequently, a bet placed 10 days before July 1st is weighted at half the weight of a bet placed 20 days before July 1st. If you bet 30 bitcoins one day before July 1st, you would receive the same winnings as another winner who bet 1 bitcoin 30 days before July 1st.

Make sense?

Note: my previous post in this thread has now been updated.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 07:39:10 PM
I just realized that there is no incentive to be one of the first people to bet. The first 5 people to post in this thread that they placed a bet of any size (include your address and the amount) will receive 0.1 BTC sent to the betting address from my personal wallet (not from the futures pool), to kick things off.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: mndrix on May 26, 2011, 07:50:36 PM
Hey Michael,

Would you be willing to hold a 50BTC bond for me?

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I'm always up for an experiment.  dacoinminster, you can send your
50 BTC bond to 168bokgyuxUYp1HL7xeyZzQCj7dEKZQyuR

I've signed with my OTC key so people who don't know me can
decide whether I'm trustworthy
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (Darwin)

iQEcBAEBAgAGBQJN3q7kAAoJEM5SyYpICBmRZQEH/2kKlWZcrJU3t8YS/7s390oo
8rYQlgonhOH5ss86UZxXJKO0LyXtwHOsrjZ9+GqVKdQoFNcc9KdtI0Sr2g9LXNor
eTBDDi0puSyTdTVKUeOpYm/lKqae24OI/iDYnD08dqQy4LyS/9q4UZqKWrRMTwi8
JGW5ki3rQ2R1EnAMYavqOFkNyK/6E21XM/rlKgHCEd3VUrOLZo59Kp1l7/ICgDfK
X5O+lTk7vyIdJ18TyF6lwbRb7d6gN8jA6sMIT4tADRnv+d90EnvhEf8OyK6Q6y9y
iDmZCm0iTg5ngk34a5Pf9asPDI++zeaJZWRCvllhePNFdI0FrDp39oE15ADRNjc=
=GcpL
-----END PGP SIGNATURE-----


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 08:10:59 PM
50 BTC sent. You can view the bond here: http://blockexplorer.com/address/168bokgyuxUYp1HL7xeyZzQCj7dEKZQyuR

I can't think of any reason why it woudn't be safe to place bets now. Let me know if you guys can think of any other problems.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: bitcoinfrenzy on May 26, 2011, 09:39:22 PM
Another question.  Will you post updates of the bets you receive with BTC amount and guess?  For the sake of transparency, this may be a good idea. 


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: FreeMoney on May 26, 2011, 09:45:08 PM
This is interesting. I plan to play, gotta get some strategery first.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 09:46:09 PM
Another question.  Will you post updates of the bets you receive with BTC amount and guess?  For the sake of transparency, this may be a good idea. 

All bets are publicly visible here: http://blockexplorer.com/address/1945qfobZxdnmVJ6qBd4FgcVcWBhDXKiTV

Probably anybody who bets should also post it here so that previous betters get notified by the forum, and this thread stays more visible to other potential betters who might give you their money :)


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: Maged on May 26, 2011, 09:57:23 PM
I'll kick things off...

I bet 0.097 btc that the price will be $9.70. Yeah, it's a small bet, but that's still a month out.

It's coming from 1NptwUa4wFNUXPyhQ8wsS54s36QeTPaJYK


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 10:02:28 PM
Quote
What if another exchange service becomes more popular than MtGox OR MtGox is not available on July 1st?

I'll use the best data available from the biggest exchange running. If for some reason winners cannot be chosen in a way that seems fair to me, I will just return all bitcoins to the original betters.

Quote
And how can I bet that bitcoins will be worth >$99?  ???

Buy some bitcoins :)


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: FreeMoney on May 26, 2011, 10:02:40 PM
A quirk of this system is that if the price happens to be low and stable near the deadline it will be easy for late bets to win. Say it's been $2-$2.50 for a week it's easy money 1 day out (possibly to the point of bets only being limited by people's fear of you running with 10k+ bets, haha or fear of manipulation at the last second). But if it is more stable and high, say $21-$23 it takes multiple bets to cover the range.

Not saying you should change anything, it's an interesting game.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 10:08:50 PM
I'll kick things off...

I bet 0.097 btc that the price will be $9.70. Yeah, it's a small bet, but that's still a month out.

It's coming from 1NptwUa4wFNUXPyhQ8wsS54s36QeTPaJYK

I see it in block explorer. I sent 0.1 BTC to your address. 4 more people are gonna get the freebie!


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 10:11:01 PM
A quirk of this system is that if the price happens to be low and stable near the deadline it will be easy for late bets to win. Say it's been $2-$2.50 for a week it's easy money 1 day out (possibly to the point of bets only being limited by people's fear of you running with 10k+ bets, haha or fear of manipulation at the last second). But if it is more stable and high, say $21-$23 it takes multiple bets to cover the range.

Not saying you should change anything, it's an interesting game.

If I do this again, maybe I'll do +/- 5% instead of +/- $0.50 to win.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: jack102938 on May 26, 2011, 10:14:26 PM
I just bet 0.1 btc that the price will be $10.

It's coming from 16rdqfvMxgArJXZ28RR91t3HiJDhmuitjJ


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 10:29:00 PM
The two jokers above just got their free money. 0.2 BTC left to give away.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: error on May 26, 2011, 10:58:02 PM
I just sent in my guess. It will make some of you choke on your drink.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: fadisaaida on May 26, 2011, 10:59:30 PM
i bet 0.17 BTC that value will be 17$.

coming from :
18wk1xCrjqCvbkfSXZVCWJu9Nn4Q74dSyc


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: Maged on May 26, 2011, 11:05:58 PM
I just sent in my guess. It will make some of you choke on your drink.
$17? Makes sense with the current increase we've seen.

I'll add $14.80 for 0.148.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: error on May 26, 2011, 11:23:26 PM
i bet 0.17 BTC that value will be 17$.

coming from :
18wk1xCrjqCvbkfSXZVCWJu9Nn4Q74dSyc

Copycat. (http://blockexplorer.com/tx/a209b6df014c887112a7b4dd9b83e0af6f34ddb238aa0a863728b00b75cb706d)


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 11:24:14 PM
I just sent in my guess. It will make some of you choke on your drink.

His guess was 0.173 bet on $17.30 (you can see it in the blockexplorer link). I sent him 0.1 BTC at 1EmT2SDdKwp8Zhz3RngEHzAyBtfR5E3Usu

i bet 0.17 BTC that value will be 17$.

coming from :
18wk1xCrjqCvbkfSXZVCWJu9Nn4Q74dSyc

According to blockexplorer, the 0.17 bet actually came from 1AMutUVeYKoePyuUNGn8dkVB7HWYCtvjKr, which is where I sent the 0.1BTC. I'm presuming it got to you alright.

And that's it for free money!

This is fun!


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: bitcoinfrenzy on May 26, 2011, 11:25:29 PM
What if nobody wins?


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 11:27:55 PM
What if nobody wins?

If you saw that nobody was going to win, wouldn't you send a tiny bet to all possible values $1 apart?

Still even if that happened somehow, I'd just give the money back to everyone.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: fadisaaida on May 26, 2011, 11:29:03 PM
I just sent in my guess. It will make some of you choke on your drink.

His guess was 0.173 bet on $17.30 (you can see it in the blockexplorer link). I sent him 0.1 BTC at 1EmT2SDdKwp8Zhz3RngEHzAyBtfR5E3Usu

i bet 0.17 BTC that value will be 17$.

coming from :
18wk1xCrjqCvbkfSXZVCWJu9Nn4Q74dSyc

According to blockexplorer, the 0.17 bet actually came from 1AMutUVeYKoePyuUNGn8dkVB7HWYCtvjKr, which is where I sent the 0.1BTC. I'm presuming it got to you alright.

And that's it for free money!

This is fun!

strange i see the incoming 0.1 from you but my client still give me that my key is : 18wk1xCrjqCvbkfSXZVCWJu9Nn4Q74dSyc


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 11:31:08 PM

strange i see the incoming 0.1 from you but my client still give me that my key is : 18wk1xCrjqCvbkfSXZVCWJu9Nn4Q74dSyc

Yeah, that's your receiving address. Your sending address is usually an address where you have gotten your coins in the past.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 26, 2011, 11:48:12 PM
Somebody just bet 2.08 BTC on $8 bitcoins in July. Biggest bet by far so far.

edit: Now there's a 2.09 BTC bet on $9 bitcoins too

Not a bad "strategery" at this stage, if you ask me!


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 27, 2011, 05:21:08 PM
Another bet came in: 0.18 put on $18/bitcoin on July 1st.

5.138 BTC is now in the pot to be won.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: matsh on May 30, 2011, 07:41:12 AM
Just bet 0.13.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: jibjabz on May 30, 2011, 11:02:44 AM
So anything over $10 is only bet in whole dollar USD right?


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: FreeMoney on May 30, 2011, 11:12:12 AM
So anything over $10 is only bet in whole dollar USD right?

No you could bet on USD/BTC of 10.50 by sending 1.105BTC.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: slowmining on May 30, 2011, 11:19:38 AM
0.09 sent.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on May 31, 2011, 09:12:01 PM
At the blockexplorer.com link in post #1 I see two bets not listed here (0.11 and 0.12)

Pot is now 5.658 BTC


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 01, 2011, 11:39:36 PM
I personally think that most of you guys have numbers that are too low, but I promised I wouldn't bet my own bitcoins here. Sigh.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: bitoption on June 02, 2011, 04:23:24 AM
You can pay 4 BTC for guaranteed right to buy at $12  on August 4 at bitoption.org right now: https://bitoption.org/securitiesList

(Just a plug. Web interface coming soon)


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: bitoption on June 03, 2011, 11:10:41 PM
And, it's up: https://bitoption.org


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: broker11 on June 05, 2011, 02:06:05 AM
Why not close the bidding at some point before the prediction date?


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 05, 2011, 04:24:19 AM
Why not close the bidding at some point before the prediction date?

I suppose I could do that if I do another round. I don't want to change the rules partway in.

I would like to point out that ALL the early guesses were too low if current prices hold :)


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: FreeMoney on June 05, 2011, 09:19:37 AM
I just sent in my guess. It will make some of you choke on your drink.

Why? Because it is so low? :P


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 07, 2011, 03:51:35 PM
Somebody placed a bet on $34 bitcoins on July 1st. Wow.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 08, 2011, 03:13:10 PM
Holy cow, and we're already almost there! $34 may not be high enough!

Earlier in this thread, I jokingly said that if you want to speculate on prices higher than $99 by July 1st, just buy bitcoins. Now I have to decide if I can provide a mechanism to do so. Any ideas? Should I just expand the range to include values up to 1.99 BTC? 2.99 BTC? (Obviously that would only apply to bets posted after the change is announced).


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: freequant on June 10, 2011, 07:50:08 PM
Finally are you going to pick the winners in a range of +/- $0.5 around the last, or +/- 5% as you suggested later?
To be fair with people who don't bother reading the whole thread, rules should be set once and for all, but that's your call.
Is the limit inclusive? For instance, if I have one bet at $5 and one at $6, and the final price falls on $5.5, are both of my bets included in the +/- $0.5 range and both accounted for to calculate my share in the payoff?


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 10, 2011, 08:00:31 PM
Finally are you going to pick the winners in a range of +/- $0.5 around the last, or +/- 5% as you suggested later?
To be fair with people who don't bother reading the whole thread, rules should be set once and for all, but that's your call.
Is the limit inclusive? For instance, if I have one bet at $5 and one at $6, and the final price falls on $5.5, are both of my bets included in the +/- $0.5 range and both accounted for to calculate my share in the payoff?

The 5% thing was a "maybe for next time" idea. The rules are set in post #1 and will not change, except as needed for clarification.

Regarding inclusive bets, that is a good question which is not addressed in post #1. I doubt that situation will arise, but if it does, I think I HAVE to make them inclusive. It's much better to have an extra winner than to have someone be exactly $0.50 away and be excluded by a technicality.

Post #1 has been updated accordingly. It now says:

Quote
a) 98% of the pot will go to the winners (those within + or - $0.50 of the final value, inclusive)


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: netrin on June 23, 2011, 01:59:19 PM
I wish I ran into this thread earlier, but none the less, dacoinminster, I'm happy you've shared your thoughts with us. Your use of the decimal component to set the bid position is simple and clever.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 23, 2011, 03:14:20 PM
I wish I ran into this thread earlier, but none the less, dacoinminster, I'm happy you've shared your thoughts with us. Your use of the decimal component to set the bid position is simple and clever.

Thanks! There have been some websites which have sprung up to fill this need since I started this thread, but there are still 6 unclaimed bitcoins in the pot, so I updated the thread title to hopefully get some attention that this contract will be ending soon.


Title: Re: Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 28, 2011, 11:55:46 PM
Somebody is submitting a lot of bets in the last few hours. I think all the "nearby" prices now have at least one winner registered.

I see bets at $16, $19, $20, $21, $22, and $23. Probably all by the same person who would probably rather I not bump this thread (sorry!)

Pot is now 7.2 BTC


Title: Re: 7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: error on June 29, 2011, 01:37:58 AM
Ah, I was looking for this thread last night. Maybe my prediction will turn out to be true after all.


Title: Re: 7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: netrin on June 29, 2011, 02:33:48 AM
Quote
c) The pot will be split among winners by the size of their bet multiplied by the number of days in advance they made their bet (days will be fractional with resolution in seconds, per block explorer timestamps)

Does 'the pot' include ALL bets or only loosing bets? I believe if the pot is ALL bets (typically parimutuel) then late winners can LOOSE (shown below) and if late bids are high enough, early winners can loose.

A 1 btc LOOSING bid, 10 days in advance
B 9 btc WINNING bid, 10 days in advance (90% risk/confidence)

C 10 btc WINNING bid, 1 day in advance

Payout if pot=TOTAL (winning bids + loosing bids)
A = 0 btc
B = 20*90/100 = 18 btc (100% gain)
C = 20*10/100 = 2 btc (80% loss)

I believe it is only fair to return the winning wagers and then calculate the profits amongst the winners.

Payout if pot=LOOSERS (loosing bids only)
A = 0 btc
B = 9+1*90/100 = 9.9 btc (10% gain)
C = 10+1*10/100 = 10.1 btc (1% gain)



Title: Re: 7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 29, 2011, 11:36:35 PM
You are correct that a late entry can lose money even if they guess correctly, but that is only true if they are late enough and there aren't many losing bets. That is intentional.

I'm pretty sure it is not possible for a late bet to cause an earlier winning bet to lose money. Here is my example:

A bets 2 BTC 10 days in advance, loses
B bets 2 BTC 10 days in advance, wins
C bets 10000 BTC 1 day in advance, wins

The pot is 10004 BTC.
I would get my 2% fee = ~200 BTC, winners get 98% = ~9804 BTC

A gets nothing (loser!)
B's weight is 10 days * 2 BTC = 20
C's weight is 1 day * 10000 BTC = 10000
Total of weights = 10020

B's share is 20/10020 = 0.2% (19.57 BTC, a 10x gain)
C's share is 10000/10020 = 99.8% (9784 BTC, oops!)

Of course, in reality there will be a lot of losers, and only a couple winners, so I expect all winners will do well as long as they didn't bet an absurdly high number of BTCs. Doing that only helps me :)

It's possible that there IS some way to game the system, but I haven't thought of one. This is an experiment. If anybody can see a way to cheat, definitely post your idea (or just go ahead and cheat, and I'll try to figure out what to do about it).




Title: Re: 7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: fadisaaida on June 30, 2011, 12:10:06 AM
how long is this going to last ? i can't believe im the closest one to the value with my 0.17 bet from 05-26 :)


Title: Re: 7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: netrin on June 30, 2011, 01:18:29 AM
I'm pretty sure it is not possible for a late bet to cause an earlier winning bet to lose money.

I stand corrected.

However, your system might penalize winners by discouraging new losers (although also discouraging competition, which you'll probably correctly argue is a bigger fear of a early better) because there is little incentive to bet on a position if it is already taken (whether eventually winning or loosing).

Depending on a bet, there are likely more loosing positions than winning positions, so everyone should want an inflated market as long as at no moment is there a position of greater than 50% assurance. If you close the bet well in advance of the moment-of-reckoning, I think your winners would have appreciated more volume. Obviously if you allow betting until the moment-of-reckoning (with no winners loosing) then all bets will accelerate toward the winning position, thus deflating the early winning bids.

I write this forty hours before the close. I've got coins burning in my wallet, but can not rationally choose a position that comes close to the risk (though, I admit the market has shown abnormally low volatility the last three days). On second thought...


Title: Re: 7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on June 30, 2011, 01:18:40 PM
how long is this going to last ? i can't believe im the closest one to the value with my 0.17 bet from 05-26 :)

Yeah, it looks like you might do pretty well in this contest!

I write this forty hours before the close. I've got coins burning in my wallet, but can not rationally choose a position that comes close to the risk (though, I admit the market has shown abnormally low volatility the last three days). On second thought...

Hmmm. Somebody just bet 1.175 BTC on $17.50 :)


Title: Re: 7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: netrin on June 30, 2011, 03:49:53 PM
I write this forty hours before the close. I've got coins burning in my wallet, but can not rationally choose a position that comes close to the risk (though, I admit the market has shown abnormally low volatility the last three days). On second thought...
Hmmm. Somebody just bet 1.175 BTC on $17.50 :)

An optimistic moron if you ask me. :)


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on July 01, 2011, 04:31:50 PM
Today is the day. This should be interesting. There's a new bet of 1.165 BTC placed on $16.50. Current price is $16.

There was a bet on 9/28 of 0.16 BTC on $16, and that person will be the only winner as of now if the price falls under $16. I note that if the price falls under $15.50 before noon today pacific time (2.5 hours from now), there is currently no winner, although I'm sure someone would make a last-minute bid to collect some free BTC if that happened. There are plenty of bets waiting to collect if the price goes up.

I should maybe point out though, that a bet placed 2 hours before this is over is weighted twice as highly as a bet placed 1 hour before it is over :)

I updated post #1 because I will be offline over the holiday weekend through Monday. I'll be posting the winners and win amounts (by my calculations) here today, and will be distributing the coins TUESDAY if there is no controversy. If there is controversy, I will respond and allow more time for comments to come in before I make payments.



Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on July 01, 2011, 05:28:56 PM
Looking at the blockexplorer log, it appears that the timestamps are UTC. Pacific Time is currently -7 hours from that (we are in pacific daylight time right now). I noticed that at one point in my original post I said the time would be "PST" which is not technically correct since right now my clock is running in "PDT". I have updated post #1 to just say "pacific time" now, because I did not mean to imply that I would be ignoring the daylight saving adjustment.

On blockexplorer timestamps, this contest ends: 2011-07-01 19:00:00 (12+7=19)

The 1.165 BTC bet came in at 2011-07-01 11:26:44 UTC which was 7 hours, 33 minutes, 16 seconds early, which is 0.31476851851851... days early. If that bet is a winner, its weight will be 1.165*0.31476851851851... = 0.36670532407407407...

The 0.16 bet came in at 2011-06-28 09:03:50 UTC which was 3 days, 9 hours, 56 minutes, 10 seconds early, which is 3.414004629629629... days early. If that bet is a winner, its weight will be 0.16*3.414004629629629... = 0.5462407407407...

I calculate that any more winning bets placed at this time would definitely be unprofitable (unless the price falls below $15.5). At this point, the pot is 9.743 BTC. My 2% is 0.19486 BTC (which does not cover the 0.5 BTC I gave away to inspire early betting), leaving 9.54814 BTC to be split among the winners according to their weights.

Edit: Fixed several mistakes in the calculations above. I will look for at least one person to double-check my math before this is all over.


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on July 01, 2011, 07:05:34 PM
The price has been dancing perilously close to $16 over the past couple hours. I used https://mtgox.com/trade/history to see that:

Price at 11:55:00 was 16.06869
Price at 11:56:00 was 16.06869
Price at 11:57:00 was 16.06869
Price at 11:58:00 was 16.06869
Price at 11:59:00 was 16.0007
Price at 11:59:30 was 16.0007
Price at 11:59:45 was 16.0007
Price at 11:59:55 was 16.0007
Price at 12:00:00 was 16.0007
Price at 12:00:05 was 16.0007
Price at 12:00:15 was 16.0007
Price at 12:00:30 was 16.0007
Price at 12:01:00 was 16.0007
Price at 12:02:00 was 16.03
Price at 12:03:00 was 16.03
Price at 12:04:00 was 16.03
Price at 12:05:00 was 16.04

Wow. That was incredibly close. If the price had slipped below $16, the 1.165 BTC bet wouldn't have gotten anything!

The two bets described in my last post are the two winners. They have a combined weight of 0.91294606481481481...

The 0.16 BTC bet came from 16eg1Qs15Vq7mvpi2fPNQuYzBkhp5DhzNq, which gets 0.5462407407407... / 0.91294606481481481... = 59.83275% of the winnings, which I'll round up to 5.72 BTC (more than 35x gain!)

The 1.165 BTC bet came from 1NsvfVxNHzoz484aTSeutayTwGi6VQmqYL, which gets 0.36670532407407407... / 0.91294606481481481 = 40.16725% of the pot, which I'll round up to 3.84 BTC (more than 3x gain!)

I would like at least one person to double-check my math. Please take a look at the timestamps here: http://blockexplorer.com/address/1945qfobZxdnmVJ6qBd4FgcVcWBhDXKiTV, the rules in post #1, my calculations in this post and the last one, and try to reproduce my calculations. Post your results confirming or correcting my calculations in this thread. If nobody confirms/corrects my calculations, you guys are going to be stuck with them!

As described earlier, payments will be made Tuesday 7/5 if there is no controversy about any of this.



Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on July 01, 2011, 08:01:34 PM
I realized I can actually download the trades for the time period above from the list of recent trades here: http://mtgox.com/code/data/getTrades.php

Here's the most interesting/relevant chunk of data:

{"date":1309546534,"price":"16.06869","amount":"0.1","price_int":"1606869","amount_int":"10000000","tid":"1309546534570843"}{"date":1309546714,"price":"16.06869","amount":"0.70603902","price_int":"1606869","amount_int":"70603902","tid":"1309546714395447"}{"date":1309546714,"price":"16.065","amount":"19.79800996","price_int":"1606500","amount_int":"1979800996","tid":"1309546714419664"}{"date":1309546714,"price":"16.05011","amount":"0.15","price_int":"1605011","amount_int":"15000000","tid":"1309546714475023"}{"date":1309546714,"price":"16.05","amount":"1.18","price_int":"1605000","amount_int":"118000000","tid":"1309546714499844"}{"date":1309546714,"price":"16.0234","amount":"1","price_int":"1602340","amount_int":"100000000","tid":"1309546714528446"},
{"date":1309546714,"price":"16.02001","amount":"1","price_int":"1602001","amount_int":"100000000","tid":"1309546714548907"},
{"date":1309546714,"price":"16.011","amount":"2.23962072","price_int":"1601100","amount_int":"223962072","tid":"1309546714566519"},
{"date":1309546714,"price":"16.01","amount":"50","price_int":"1601000","amount_int":"5000000000","tid":"1309546714601679"},
{"date":1309546714,"price":"16.0007","amount":"13.91720362","price_int":"1600070","amount_int":"1391720362","tid":"1309546714633848"},
{"date":1309546714,"price":"16.0007","amount":"10.94612668","price_int":"1600070","amount_int":"1094612668","tid":"1309546714691336"},
{"date":1309546857,"price":"16.05101","amount":"1","price_int":"1605101","amount_int":"100000000","tid":"1309546857305532"},

Using a handy unix timestamp converter (http://www.onlineconversion.com/unix_time.htm), I come up with the following sequence of events:

Fri, 01 Jul 2011 18:55:34 GMT: Somebody buys 0.1 BTC at 16.06869
Fri, 01 Jul 2011 18:58:34 GMT: Somebody sells 100.937 BTC all at once, driving the price down to 16.0007
Fri, 01 Jul 2011 19:00:57 GMT: Somebody buys 1 BTC at 16.05101

It's probably a coincidence, but we can't really know for sure. If someone was trying to manipulate the outcome with the big sell, they failed. It could also be that one or more of the buy orders in place right above $16 which stopped the price from going under were also trying to manipulate the outcome, in which case they succeeded. :)


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: error on July 01, 2011, 08:23:25 PM
The price is still bouncing around $16, so I don't think they were manipulating the price specifically for this. I'm just annoyed that it didn't get back up to $17.30 so I could win. :(


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: netrin on July 01, 2011, 08:42:50 PM
As the lucky, late, and optimistic moron at $16.5 I'd like to thank Dacoinminster for an entertaining run and in particular, I thank all the losers who took the time and cost to pay the boss. Since I would have been the only one to have benefited from the price above $16 and Mr. 16eg1Q to have benefited from a price below, I can only conclude that we have a market manipulator among us! I can assure you, I have done everything I could since I bought coins months ago, to keep the price as high as possible. I am therefore happy the market agrees with (albeit much lower than) my greatest expectations.

Thank you, thank you, thank you. With my winnings I shall take my girlfriend and two other ladies out for a luxurious coffee (Mr. 16eg1Q if you'd like to join us up where the sun don't set, we'd love to share a cup under the midnight sun). I owe my warm caffeinated happiness to all of you. Thank you.

Dacoinminster, I'd like to propose, should you administer a similar bet again, that you set a closing time on wagers followed by perhaps an hour during which a volume weighted average is calculated, rather than a discreet closing price. I expect a VWAP would be impractical or too costly to manipulate. I think (as long as you are dividing by the total pool rather than the loosing bids) there will always be a variable period after which betting will be unprofitable. So, setting a close time well before the VWAP period would have no negative consequence on the game.

I continue to recommend a compromise to the parimutuel. Perhaps the winnings pool is composed of 100% of the loosing bids and some percentage (50% ?) of the winning bids. And/or weighting by the square (or ^1.5) of the time. I expect these changes would secure early bidders with a great advantage (encouraging early bids) while minimally discouraging later bids, thus increasing the volume throughout the betting period. And more profits for graceless jerks like me and Mr. Market Manipulator 16eg1Q. :)

EDIT: Because there will be a period of lost winning bets, a closing time before determination and payout will not be necessary. I think it is safe to start the VWAP period before the final close of the market. For example, all bets must be in by 24:00 UTC, where the VWAP is calculated 23:00-24:00 UTC. Betters will likely loose if they wager before 23:00 and I suspect will loose with wagers much earlier still.


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: error on July 01, 2011, 08:46:29 PM
I agree that bets should be closed at least a few days before the time rolls around.


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: netrin on July 01, 2011, 09:28:26 PM
I agree that bets should be closed at least a few days before the time rolls around.

Well, I wouldn't say "days". That would be pure hazard, fit for drunken gamblers, not nuanced gentlemen and ladies like ourselves. I think what we should be aiming for is a price spread that 'predicts' the future market. You must give a sufficient advantage (I say time^2) to early bids, but ideally you should allow for a market to approach the limit of 100% certainty (while rapidly approaching 0% gain).


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: netrin on July 02, 2011, 03:47:26 AM
The 0.16 BTC bet came from 16eg1Qs15Vq7mvpi2fPNQuYzBkhp5DhzNq, which gets 0.5462407407407... / 0.91294606481481481... = 59.83275% of the winnings, which I'll round up to 5.72 BTC (more than 35x gain!)

The 1.165 BTC bet came from 1NsvfVxNHzoz484aTSeutayTwGi6VQmqYL, which gets 0.36670532407407407... / 0.91294606481481481 = 40.16725% of the pot, which I'll round up to 3.84 BTC (more than 3x gain!)

I would like at least one person to double-check my math.

I used the seconds throughout the calculation and came to the same results:

close time in seconds: 1309521600
total winning weight: 78878.540 = 31683.340 + 47195.200
winnings after commission: 9.5481 = 9.743 * (1 - 0.02)

address: 6eg
wager: 0.160
bid time: 1309226630
weight: 47195.200 = (1309521600 - 1309226630) * 0.160
payout: 5.7128 = 9.5481 * 47195.200 / 78878.540

address: Nsv
wager: 1.165
bid time: 1309494404
weight: 31683.340 = (1309521600 - 1309494404 ) * 1.165
payout: 3.8352 = 9.5481 * 31683.340 / 78878.540



Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: TiagoTiago on July 02, 2011, 04:01:59 AM
Interesting idea


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on July 05, 2011, 04:55:42 PM
Payments were sent this morning, but for some reason my client broke them up into a bunch of separate transactions. You can see them all here: http://blockexplorer.com/address/1945qfobZxdnmVJ6qBd4FgcVcWBhDXKiTV

The wallet had been offline for awhile, and was still downloading blocks when I sent the coins, so maybe that has something to do with it.

It appears that the two winners got the right number of coins though. Netrin, can you confirm that?

This was an interesting experiment, and parts of it may serve as a model for future systems doing similar things. Thanks for participating.


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: netrin on July 06, 2011, 02:11:55 AM
Looks good to me:
http://blockexplorer.com/address/1945qfobZxdnmVJ6qBd4FgcVcWBhDXKiTV (Betting pool)
http://blockexplorer.com/address/16eg1Qs15Vq7mvpi2fPNQuYzBkhp5DhzNq (payout 5.72 btc)
http://blockexplorer.com/address/1NsvfVxNHzoz484aTSeutayTwGi6VQmqYL (payout 3.84 btc)


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: mndrix on July 08, 2011, 04:16:24 PM
It looks like the bet was handled according to the rules.  Unless I hear otherwise, I'll release dacoinminster's bond on Monday.


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on July 08, 2011, 04:58:11 PM
It looks like the bet was handled according to the rules.  Unless I hear otherwise, I'll release dacoinminster's bond on Monday.

Thanks for holding the bond for me mndrix! Without your help, I would have just looked like I was trying to steal bitcoins :)

I created an address for receiving the bond back from you: 18CeiS44ZFP4kXdgzx3yNocwqRqyDZxghu (I will confirm that address via my personal email from which I have corresponded with you in the past)

There's probably no other forum in the world where trust matters as much as it does here. It used to be that being a "hero member" was synonymous with being trusted here, but now they are a dime a dozen. The OTC web of trust is awesome, but not much use outside of that small circle, as most people (me included) have never used it.

Having a history of projects and successful financial transactions seems to be the best way to build trust here, and that is how I decide who to trust.


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: WiseOldOwl on July 08, 2011, 05:50:57 PM


There's probably no other forum in the world where trust matters as much as it does here. It used to be that being a "hero member" was synonymous with being trusted here, but now they are a dime a dozen. The OTC web of trust is awesome, but not much use outside of that small circle, as most people (me included) have never used it.

Having a history of projects and successful financial transactions seems to be the best way to build trust here, and that is how I decide who to trust.
+1


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: mndrix on July 11, 2011, 02:15:17 PM
I created an address for receiving the bond back from you: 18CeiS44ZFP4kXdgzx3yNocwqRqyDZxghu (I will confirm that address via my personal email from which I have corresponded with you in the past)

I've returned the 50 BTC bond to 18CeiS44ZFP4kXdgzx3yNocwqRqyDZxghu in transaction dea182c9888fe6265b889453015b4826c41ce552548eec692f5740cd24b76a46


Title: Re: 9.7BTC for the taking! Bet on bitcoin future price here (July 1st, 2011)
Post by: dacoinminster on July 11, 2011, 03:03:06 PM
I've returned the 50 BTC bond to 18CeiS44ZFP4kXdgzx3yNocwqRqyDZxghu in transaction dea182c9888fe6265b889453015b4826c41ce552548eec692f5740cd24b76a46

I confirm receipt of the bond. Thanks!