Bitcoin Forum

Economy => Marketplace => Topic started by: Ian Maxwell on May 13, 2011, 03:38:53 AM



Title: Guess my baby's sex!
Post by: Ian Maxwell on May 13, 2011, 03:38:53 AM
My wife Jennifer and I are having a baby in September! Or maybe October---the due date is September 30, so there's room for it to go either way. But anyway, this is exciting!

And soon (possibly next week) we're going in for an ultrasound and finding out the sex! Even more exciting!

Do you want to use this as a way to make some quick bitcoins and help out a young couple at the same time? Then, ladies and gentlemen, place your bets.

How it works

I'm running a parimutuel betting pool on the sex of my baby. Bet as much as you want by sending bitcoins to one of the following addresses:

IT'S A BOY! at 163oWWKA3C9uQ2UHept19wEPq54JdUGKii
IT'S A GIRL! at 17Qcg9sYFuGSQSj5qPD8K7xRNfHkgNigYb

Send these bitcoins from your own wallet! If you use a service like MyBitcoin your winnings are likely to be lost!

When we find out the sex, I'll take all the bets and split them up between the addresses on the winning side, in proportion to the size of the bet. I'll also take a cut---ten percent, plus any "remainders" after people's winnings are rounded down to fit into eight decimal places. Hopefully it will be enough to help defray the exciting new expenses of being a parent!

Demo

Say the bets break down like this:
Joe bets 5 BTC on "boy"
Susan bets 2 BTC on "boy"
Ed bets 1 BTC on "girl"
Agnes bets 3.14159 BTC on "girl"

That's a total of 11.14159 BTC---7 for "boy" and 4.14159 for "girl". After I take out my 10% cut, there's 10.14159 left in the pool.

Now let's say it turns out it's a girl. Then Ed and Agnes win the pot! I split it up "equally" by sending 2.42115492 to Ed and 7.60627608 to Agnes. (Agnes bet more, so she wins more proportionally.)

On the other hand, if it's a boy, I'll send 7.16245071 to Joe and 2.86498029 to Susan. You can see that you stand to win more by being on the less popular side---it's like a metaphor for Bitcoin itself!  :D

Q&A

Why would I bet on this when BitLotto only keeps 1%?
Because that guy is spending his take on hookers and blow, and I'm spending mine on diapers and college. (In all seriousness, I'm totally cool with the lotteries and what they're doing. This is not an attempt to compete with them on equal grounds---it's more like a charity raffle in my own name.)

How do I know I can trust you?
I have a minor but positive reputation here. If you don't trust me anyway, I guess you shouldn't bet, or bet very little. Personally, I think my cut is good enough that there's no need for me to try and cheat on top of it.

Do you already have some sort of information on the sex that you're withholding?
Not a thing. I can tell you that Jennifer's family all expect a girl (because they've had a lot of boys lately), and my family all expect a boy (because they've had a lot of girls lately). She also expects a boy, but cheerfully admits it's a wild guess. I'm equally prepared(?) for either one.

I'm still not totally clear on how this works?
Then ask away!


Title: Re: Guess my baby's sex!
Post by: ataranlen on May 13, 2011, 03:50:41 AM
Congrats on the Baby! I take it this is yall's first? They're a lot of work, but soooooo worth it!


Title: Re: Guess my baby's sex!
Post by: mjsbuddha on May 13, 2011, 03:51:35 AM
even winners can be losers with this set up.

example:
mike bets 100btc on girl
john bets 1 btc on boy
steve bets 1 btc on boy
alan bets bets 1 btc on boy

you take 10% of the 103 btc which is 10.3 btc and if its a girl mike "wins" 92.7 btc when he put in 100 btc


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 13, 2011, 03:54:20 AM
Hm.... that is possible, if the bets are wildly unbalanced. I was assuming they'd be close to even between the two possibilities. If that actually happens, I guess I'll just make up the difference from my cut.

It is our first! And believe me, I'm already expecting it to be a lot of work. (I'll probably still manage to be surprised by it, though)


Title: Re: Guess my baby's sex!
Post by: Alex Beckenham on May 13, 2011, 03:56:15 AM
Do you already have some sort of information on the sex that you're withholding?
Not a thing.

Were you and your wife vertical or horizontal at conception?


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 13, 2011, 03:57:06 AM
@doood: My sex life is far too healthy for me to have a definite answer to that question.  ;D


Title: Re: Guess my baby's sex!
Post by: mjsbuddha on May 13, 2011, 03:57:12 AM
Do you already have some sort of information on the sex that you're withholding?
Not a thing.

Were you and your wife vertical or horizontal at conception?


omg... he went there...


Title: Re: Guess my baby's sex!
Post by: mjsbuddha on May 13, 2011, 03:58:34 AM
anyway, good luck with both the child and the betting pool.


Title: Re: Guess my baby's sex!
Post by: Alex Beckenham on May 13, 2011, 04:03:34 AM
When we find out the sex, I'll take all the bets and split them up...

My only request is that if possible give us all a day or two warning before you find out the sex...

Like post "We are heading for an ultrasound next Tuesday" for example.

That way everyone can get their final bets in on time.



Title: Re: Guess my baby's sex!
Post by: nanotube on May 13, 2011, 04:12:46 AM
please post picture of the pregnant belly, front and side views, not obstructed by loose-fitting clothing. :)


Title: Re: Guess my baby's sex!
Post by: mjsbuddha on May 13, 2011, 04:15:44 AM
come on guys. give the guy some privacy.


Title: Re: Guess my baby's sex!
Post by: koin on May 13, 2011, 04:23:02 AM
I'm running a parimutuel betting pool on the sex of my baby. Bet as much as you want by sending bitcoins to one of the following addresses:

Then ask away!

what about if it is twins?

do you have gpg web trust?


Title: Re: Guess my baby's sex!
Post by: nanotube on May 13, 2011, 04:28:18 AM
come on guys. give the guy some privacy.

heh, guy posts a betting pool on the sex of his baby... he's gotta expect some related queries.


Title: Re: Guess my baby's sex!
Post by: Fiyasko on May 13, 2011, 04:30:08 PM
i think he asked for ultrasound photos because he'd beable to identify the genitalia without the photo being classified as CP,
And when a baby is First born somepeople have troubles recognizing M/F.
But i think what would be the most appropriate "THIS IS PROOF" document would be a brief snapshot of the "Male/Female" part of the birth certificate


Title: Re: Guess my baby's sex!
Post by: lulzplzkthx on May 13, 2011, 04:45:15 PM
Sent! My sources better be right...


Title: Re: Guess my baby's sex!
Post by: Alex Beckenham on May 13, 2011, 11:13:22 PM
i think he asked for ultrasound photos because he'd beable to identify the genitalia without the photo being classified as CP,
And when a baby is First born somepeople have troubles recognizing M/F.
But i think what would be the most appropriate "THIS IS PROOF" document would be a brief snapshot of the "Male/Female" part of the birth certificate

Who asked for ultrasound photos?


Title: Re: Guess my baby's sex!
Post by: Fiyasko on May 14, 2011, 08:42:48 PM
i think he asked for ultrasound photos because he'd beable to identify the genitalia without the photo being classified as CP,
And when a baby is First born somepeople have troubles recognizing M/F.
But i think what would be the most appropriate "THIS IS PROOF" document would be a brief snapshot of the "Male/Female" part of the birth certificate

Who asked for ultrasound photos?


/facepalm

Why did i ever think ultrasound?, LoL!


Title: Re: Guess my baby's sex!
Post by: tomcollins on May 15, 2011, 01:22:42 AM
This is way too easy to scam.  Figure out sex.  Have some "anonymous" people bet on the winning side.  Profit.

I'm sure you are probably a reputable guy and all, but something like this where insider knowledge completely crushes the bet is super easy to scam.


Title: Re: Guess my baby's sex!
Post by: kgo on May 15, 2011, 01:55:51 AM
Well the payout should be close to double-or-nothing if there are enough bets.  It's be easy to tell if the fix was in.  Unfortunately not until after the event.


Title: Re: Guess my baby's sex!
Post by: tomcollins on May 15, 2011, 02:12:41 AM
Well the payout should be close to double-or-nothing if there are enough bets.  It's be easy to tell if the fix was in.  Unfortunately not until after the event.

Not necessarily.  If too many people bet on one side, I bet new betters would take the other.  So you make your bets early enough that it evens out by people trying to get a "better" deal, then it doesn't look suspicious.

Don't mean to be paranoid, just seen The Sting.


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 18, 2011, 03:21:27 PM
Guys, this may be the last day! My wife and I are going for her 20-week checkup today (a bit late). They haven't actually said we're getting an ultrasound today, but they haven't said we aren't, either. So if you want to place a bet, best do so now!


Title: Re: Guess my baby's sex!
Post by: abyssobenthonic on May 19, 2011, 01:04:54 AM
Well the payout should be close to double-or-nothing if there are enough bets.  It's be easy to tell if the fix was in.  Unfortunately not until after the event.

Not necessarily.  If too many people bet on one side, I bet new betters would take the other.  So you make your bets early enough that it evens out by people trying to get a "better" deal, then it doesn't look suspicious.

That's if he publishes running bet totals.  If he doesn't, then the typical bettor would have no idea of which side is underbet.


Title: Re: Guess my baby's sex!
Post by: Alex Beckenham on May 19, 2011, 01:12:57 AM
^^ shhhh... don't anyone tell this guy about the block chain ;)


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 19, 2011, 05:07:37 AM
Well, it wasn't today, but it should be some time next week. We'll probably be told the date of our ultrasound appointment tomorrow.

doood is right: you can just use BlockExplorer to see the running totals. Here are all the boy bets (http://blockexplorer.com/a/36iNnRTv5f) and girl bets (http://blockexplorer.com/a/3fUYPiofF2). (Note that I accidentally used a previously-used address for the boy bets, as the transaction record shows...)

As you can see, not much activity... at this rate, my cut is 0.13, and that's assuming the books balance themselves out before the end.

This hasn't gotten very much of a response at all, so I'll just point out that at the moment the books are unbalanced! There's a total of 0.1 riding on "boy" vs. 1.25 riding on "girl". Someone ought to come in and balance this out and make a positive expected profit in the process!


Title: Re: Guess my baby's sex!
Post by: Alex Beckenham on May 19, 2011, 05:58:21 AM
I'm the one that bet 1 btc on it being a girl... at this point by the current rules I stand to lose 0.038 btc even if it is a girl!

Let's hope others come to the party and even up the sides :)

Anyway, you'll be able to spend your profits on 0.0004 of a disposable nappy.


Title: Re: Guess my baby's sex!
Post by: abyssobenthonic on May 25, 2011, 12:45:48 AM
^^ shhhh... don't anyone tell this guy about the block chain ;)


That's why unique addresses are a must ;)


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 25, 2011, 01:49:27 AM
Books are currently at 0.4 to 1.25...

And we're finding out around 18:30 (UTC)! I'll wait until midnight to post the answer, though.


Title: Re: Guess my baby's sex!
Post by: Basiley on May 25, 2011, 03:26:34 AM
F+M twins ? :)


Title: Re: Guess my baby's sex!
Post by: Tukotih on May 25, 2011, 08:55:33 AM
F+M twins ? :)
Yeah, what the fuck will happen then? :P


Title: Re: Guess my baby's sex!
Post by: kseistrup on May 25, 2011, 09:00:17 AM
50:50


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 25, 2011, 11:39:59 AM
D'oh. Is there a "don't send from this address" option somewhere in the client?

Counting up just the "received" totals since this thread started, it's now 1.29:1.25. So nearly even.


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 26, 2011, 03:48:58 AM
It's a boy!

Winnings will be distributed as soon as I can figure out how sendmany works.


Title: Re: Guess my baby's sex!
Post by: Alex Beckenham on May 26, 2011, 07:37:04 AM
It's a boy!

Congratulations!


Title: Re: Guess my baby's sex!
Post by: N12 on May 26, 2011, 07:40:17 AM
It's a boy!
Bitcoin’s gender distribution had to stay intact, after all. ;D

Congrats.


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 26, 2011, 03:39:59 PM
All right, forget sendmany, I just sent out a bunch of separate transactions.


Title: Re: Guess my baby's sex!
Post by: niooron on May 27, 2011, 02:17:53 AM
Received my 0.08 bitcoins. I had bet 0.05 on boy and girl...


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 27, 2011, 02:56:55 AM
Received my 0.08 bitcoins. I had bet 0.05 on boy and girl...
Well, it was really unlikely you'd make money that way. You were basically not betting on the outcome, but rather meta-betting that the books would be lopsided by well more than 2:1. They weren't very lopsided, so you lost.


Title: Re: Guess my baby's sex!
Post by: kseistrup on May 27, 2011, 06:07:10 AM

All right, forget sendmany, I just sent out a bunch of separate transactions.

The sendmany() doesn't look that hard:

Code:

$ bitcoind help | grep ^sendmany
sendmany <fromaccount> {address:amount,...} [minconf=1] [comment]
$


I bet on a boy and have received my prize.  Thanks!

Cheers,


Title: Re: Guess my baby's sex!
Post by: Ian Maxwell on May 27, 2011, 06:43:46 AM
The sendmany() doesn't look that hard:

It doesn't, does it? But I tried typing it in two or three different ways and got an error each time.


Title: Re: Guess my baby's sex!
Post by: Alex Beckenham on May 27, 2011, 06:48:32 AM
The sendmany() doesn't look that hard:

It doesn't, does it? But I tried typing it in two or three different ways and got an error each time.

What tripped me up doing it in php was that I had to put (float) just before the send amount.

$bitcoin->sendfrom($account,$addr,(float)$amount);

Haven't tried sendmany yet.


Title: Re: Guess my baby's sex!
Post by: spleeder on May 31, 2011, 10:25:58 AM
I'm not having luck using 'sendmany' from PHP. Did anyone manage to get it working?