official-britcoin readded to bitcoincharts/bitcoinwatch even with "absurd data"

[mizerydearia]

Britcoin no longer listed at http://bitcoincharts.com/ and http://bitcoinwatch.com/ because tcatm considers a valid, yet extreme, order "absurd data."

Cost / BTC: 944219654443.157
Giving: 0.00161383 BTC
Wanted: 1523810004.93 GBP

<wardearia> Hiya.  How come http://britcoin.co.uk/ and http://intersango.com/ are not on listed at http://bitcoinwatch.com/?
<censored> intersango does not have trades yet and britcoins API is broken
<wardearia> How so?
<censored> it has a strange orderbook entry (something around 9 billion GBP for 0.0016.. BTC)
<wardearia> That means the API is broken?
<censored> well not broken, but my backend refuses to parse such absurd data
<censored> people have been complaining about the invalid data so I figured it would be best to hide it until it is resolved
<wardearia> So then hide the data?  Don't delist the exchange?
<censored> that's what I did. I clicked "hide" in the backend.
<wardearia> The particular data that is related to what your backend cannot handle, not all of the data
<censored> the backend doesn't support that
<wardearia> Did you write the backend?
<censored> yes
<censored> the problem is actually pretty simple: the underlying database model is limited to 10 digits and 8 decimals. changing that would require migrating about 8 GB of data
<censored> also, other exchanges with similar absurd orders were happy when I reported them so they could fix their exchange
<censored> when did I give you permission to cross paste this on the forum anyway?
<wardearia> You didn't.  Shall I censor your name?
<wardearia> I changed it
<censored> first, you should not make anything I say in private "official" (like posting it on the forum)
<censored> so could you remove that forum post?
<wardearia> I made it "unofficial"
<wardearia> If there were a zimbabwean dollar exchange, would your site be unable to handle the data?
<wardearia> sites*
<censored> why?
<wardearia> I'm curious
<censored> should work fine
<censored> if there are problems I can still migrate the database schema
<censored> the problem with the order is more like this: if I extended the schema to allow more digits one user might discover that a decimal can have more than hundred digits and place a order for 0.00000001 BTC @ 10000000000000000000000000000000000000000000000000000000000000000 GBP. same problem again
<wardearia> Is it possible to ignore such data and continue parsing remaining data?
<censored> nope
<censored> well, technically yes, but it would break the incremental orderbook feature

In case this thread is deleted/censored, there is also http://bitcoin.witcoin.com/p/1859/britcoin-removed-from-bitcoinchartsbitcoinwatch-due-to-absurd-data


http://bitcoincharts.com/news/

Britcoin hidden

July 13, 2011, 1:41 p.m.

Because of data consistency errors britcoinGBP is currently hidden. This will be resolved soon.

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[Sultan]

I noticed this as well, and it was messing up the graph big-time. It must be a bug or something.

[phantomcircuit]

I noticed this as well, and it was messing up the graph big-time. It must be a bug or something.

There is no bug on the britcoin side, merely someone who has placed an order that is extremely unlikely to ever go through.

[BitcoinPorn]

So Britcoin needs to fix their feeds is what I gather, and they made the issue public?

I'd not accept the site either and Britcoin needs a new person to represent them, because I would not trust my money with kids, and that was the action of children.  If this is the case.  Seems like a very odd way to handle business, on a web forum.

[phantomcircuit]

So Britcoin needs to fix their feeds is what I gather, and they made the issue public?

I'd not accept the site either and Britcoin needs a new person to represent them, because I would not trust my money with kids, and that was the action of children.  If this is the case.  Seems like a very odd way to handle business, on a web forum.

Again, there is absolutely nothing wrong with the Britcoin feed.

[mizerydearia]

So Britcoin needs to fix their feeds is what I gather, and they made the issue public?

I maded it public at my own personal efforts because I don't like keeping useful/important informations private.

[BitcoinPorn]

I maded it public at my own personal efforts because I don't like keeping useful/important informations private.

lol, sorry to refer to you in third person, I did not know it was you posting this again, I did not catch that, thought this was someone just reposting this information.

I can only say if you are wanting to get on the Bitcoincharts web site, I don't believe this is the right path to do so.  I am not fully understanding still, even if not wanting to be private, why that personal conversation or chat was posted, that is going to be a huge trust issue not with those people and however their feed goes down, but with you and posting this shit twice already lol.  Not like anything important was in the messages,  it is the lack of understanding the motivation behind it is all, and it puts the whole situation in question imo.

[Bigpiggy01]

I've used Britcoin multiple times and have found absolutely NOTHING wrong with it  

There are several other sites around that have almost as absurd orders on them or have had so in the past. Whoever put that order on there meant it as a joke and it says a lot more about the peeps that have an "issue" with it than it does about the site.

[mizerydearia]

I attempted to sell 0.00161383 bitcoins for 1523810004.93 XXX currency at different exchanges.  Here are my results:

bitcoin7.com

place sell order: 0.00161383 btc for 1523810004.93 usd
Invalid amount

place sell order: 0.01 btc for 1523810004.93 usd
Invalid amount

place sell order: 0.01 btc for 152381000.49 usd
Invalid amount

place sell order: 0.01 btc for 15238100.04 usd
Invalid amount

place sell order: 0.01 btc for 1523810.00 usd
Invalid amount

place sell order: 0.01 btc for 152381.00 usd
Invalid amount

place sell order: 0.01 btc for 15238.10 usd
Invalid amount

place sell order: 0.01 btc for 1523.81 usd
Invalid amount

place sell order: 0.01 btc for 152.38 usd
Invalid amount

place sell order: 0.01 btc for 15.23 usd
Invalid amount

place sell order: 1.00 btc for 1523810004.93 usd
SUCCESS

bitcoin-central.net

place sell order: 0.00161383 btc for 1523810004.93 lrusd
Amount must be greater than 1.0 BTC

awaiting more funds to resolve

bitcoinmarket.com

maxlength restricted to 8, so not possible with this site

bitmarket.eu

awaiting account verification

btcchina.com

place sell order: 0.00161383 btc for 1523810004.93 cny
SUCCESS

btcex.com

place sell order: 0.00161383 btc for 1523810004.93 usd
BTC: Quantity is too small

place sell order: 0.01 btc for 1523810004.93 usd
SUCCESS

cavirtex.com

place sell order: 0.00161383 btc for 1523810004.93 cad
Your request could not be processed, Amount: Cannot order non positive amount

place sell order: 0.01 btc for 1523810004.93 cad
SUCCESS

exchangebitcoins.com

place sell order: 0.00161383 btc for 1523810004.93 usd
Order not placed. Quantity must be 0.01 BTC or greater.

place sell order: 0.01 btc for 1523810004.93 usd
SUCCESS

tradehill.com

place sell order: 0.00161383 btc for 1523810004.93 usd
The smallest allowable BTC amount is currently 0.0100 BTC

place sell order: 0.01 btc for 1523810004.93 usd
SUCCESS

virwox.com

place sell order: 0.00161383 btc for 1523810004.93 sll
The requested amount is below the minimum amount.  You need to exchange at least 1 BTC.

place sell order: 1 btc for 1523810004.93 sll
SUCCESS

[enmaku]

If storage is cheap enough to use decimal/numeric in your database instead of floats then why can't you spend the extra storage to max out that field when you made it in the first place. MySQL allows up to 65 digits in the decimal data type, and MS SQL allows 38. Since these are the two most common database engines you'll encounter in the wild, I'd suggest limiting orders around the least common denominator: decimal(38,8).

I've written a couple personal projects that store BTC and USD values in a database and I assure you every such field is decimal(38,8) - I'd never even consider using anything else.

[tcatm]

If storage is cheap enough to use decimal/numeric in your database instead of floats then why can't you spend the extra storage to max out that field when you made it in the first place. MySQL allows up to 65 digits in the decimal data type, and MS SQL allows 38. Since these are the two most common database engines you'll encounter in the wild, I'd suggest limiting orders around the least common denominator: decimal(38,8).

I've written a couple personal projects that store BTC and USD values in a database and I assure you every such field is decimal(38,8) - I'd never even consider using anything else.

If I did that someone will insist that entering an amount with 39 (or 66) digits is a good idea.

[mizerydearia]

tcatm argued that he delisted Britcoin due to "absurd data."

Now other markets also contain "absurd data" but they are not yet delisted at http://bitcoincharts.com/ or http://bitcoinwatch.com/ both operated by tcatm.

btcchina.com
https://btcchina.com/trade/depth (must be logged in)
http://pastebin.com/raw.php?i=ZWmav7gn (I couldn't find json output)

btcex.com
https://btcex.com/site/orders/2
http://pastebin.com/MceYWtvn

cavirtex.com
can't find public data

exchangebitcoins.com
https://www.exchangebitcoins.com/data/depth
http://pastebin.com/3NEmTqeY

tradehill.com
https://api.tradehill.com/APIv1/USD/Orderbook
http://pastebin.com/0NjNfmjQ

virwox.com
Requires POST to retrieve json data, too much effort

Will these sites that contain "absurd data" also be delisted or does tcatm have some sort of personal bias or alterior motives/incentives?

Update: Britcoin is relisted at bitcoinwatch.com and bitcoincharts.com.

Note: The only winning move is not to play.  I losted.

[BitcoinPorn]

Will these sites that contain "absurd data" also be delisted or does tcatm have some sort of personal bias or alterior motives/incentives?

Update: Britcoin is relisted at bitcoinwatch.com and bitcoincharts.com.

Note: The only winning move is not to play.  I losted.

I want to say there is a happy ending here, but every time I read this thread I pull out another wacky theory on what is going on behind the scenes with the exchange sites.   It seems you did a lot of work mizerydearia, I hope the Britcoin users appreciate it

[weex]

We at ExchangeBitcoins.com are working on this now and will post an update when it's resolved.

Edit: Resolved. These orders have been canceled, affected users notified, and we have implemented sanity checks to ensure only sensible orders can be placed in our order book.

[mizerydearia]

We at ExchangeBitcoins.com are working on this now and will post an update when it's resolved.

Edit: Resolved. These orders have been canceled, affected users notified, and we have implemented sanity checks to ensure only sensible orders can be placed in our order book.

Hello mizerydearia,

Today we received some reports of orders with very high prices/quantites that shouldn't have made it into the order book. One of them was on your account and has been cancelled.

We have since implemented some sanity checks to be sure only valid orders can be placed.

We apologize for any inconvenience. Let us know if you have any questions.

Thank you,

David Sterry, President
ExchB: 1st Bitcoin Exchange in the US
email: davids@exchangebitcoins.com
cell/text: 650-773-5942

To determine what weex/ExchangeBitcoins considers the current borderline for sanity/insanity in terms of amounts/values, I have done some benchmark testing.

Error message for 'insane' is: Order not placed. Price out of range.
INSANE Sell 0.00161383 bitcoins for us$1523810004.93
INSANE Sell 0.009 bitcoins for us$1.00/1 bitcoin
INSANE Sell 0.009 bitcoins for us$0.01/1 bitcoin
SANE Sell 0.01 bitcoins for us$1.00/1 bitcoin

I mistook selling 0.01 bitcoins for us$1 as us$1 for 0.01 bitcoins NOT us$1 for 1.0 bitcoin and then my order went through at us$13.968, but I only have us$0.1389, so there is a transaction fee (which I would have noticed if I paid attention) and therefore I will not use this site again (because I refuse to be charged for these types of transactions).  Yay for bitomat (which I am unaffiliated with) and a few other exchanges with no transaction fees!

Note: I am newbie trader

[Sultan]

Nothing is wrong with BritCoin itself, but there must be SOMETHING wrong when it is reporting that a sale was made where somebody paid 10,000 pound for a BitCoin, I am certain that sale never went through or was for a small amount of BitCoins, it shouldn't have even got matched in the first place!

All the erroneous data needs to be cleaned out, when you look at BitCoin Charts and display the last 60 days' activity for BritCoin its all skewered because of this rubbish data!

[mizerydearia]

Nothing is wrong with BritCoin itself, but there must be SOMETHING wrong when it is reporting that a sale was made where somebody paid 10,000 pound for a BitCoin, I am certain that sale never went through or was for a small amount of BitCoins, it shouldn't have even got matched in the first place!

All the erroneous data needs to be cleaned out, when you look at BitCoin Charts and display the last 60 days' activity for BritCoin its all skewered because of this rubbish data!

I think it was an open ask order and not a completed trade.

[FreeMoney]

No one is entitled to space on bitcoinwatch or any other page. I don't want to see 8 or 10 or 20 digit orders and I appreciate bitcoincharts shielding my innocent eyes from the obscenity.

P.S. if anyone is interested I'm buying coins. 800BTC for .04 cents. Please relay this offer on any relevant websites.

[zebedee]

Nothing is wrong with BritCoin itself, but there must be SOMETHING wrong when it is reporting that a sale was made where somebody paid 10,000 pound for a BitCoin, I am certain that sale never went through or was for a small amount of BitCoins, it shouldn't have even got matched in the first place!

All the erroneous data needs to be cleaned out, when you look at BitCoin Charts and display the last 60 days' activity for BritCoin its all skewered because of this rubbish data!

No, they really happen; I had one myself (not at that crazy rate though).

Their software is buggy; user beware!

Unfortunately if you point out this bug to Britcoin they fob you off.

[dooglus]

Nothing is wrong with BritCoin itself, but there must be SOMETHING wrong when it is reporting that a sale was made where somebody paid 10,000 pound for a BitCoin, I am certain that sale never went through or was for a small amount of BitCoins, it shouldn't have even got matched in the first place!

All the erroneous data needs to be cleaned out, when you look at BitCoin Charts and display the last 60 days' activity for BritCoin its all skewered because of this rubbish data!

No, they really happen; I had one myself (not at that crazy rate though).

Their software is buggy; user beware!

Unfortunately if you point out this bug to Britcoin they fob you off.

Their software is buggy and I've offered a fix for it several times now.

The problem is that decisions are made based on how much you are still wanting, rather than the original price you requested.

Genjix has claimed that the 'want' field isn't actually used any more:

You're right, we do ignore the want field. It's mostly left for display and is kind of redundant. It's not even needed.

but I think he's mistaken.  The 'want' field is still used, and is exactly what's causing the problem.

Here are some examples that show how very low and very high priced trades happen:


This is how very low priced trades happen:

User A has 50 GBP and wants 5 BTC (buying BTC at 10 GBP/BTC)
User B has 6 BTC and wants 54 GBP (selling BTC at 9 GBP/BTC)

User A's order goes in first, and is unmatched.
User B's order goes in 2nd, and is partially matched at User A's rate of 10 GBP/BTC.
User B gives 5 BTC to user A and gets 50 GBP in exchange.
User B now has 1 BTC and the 'wants' value is updated to 4 GBP.

User C can now come along and buy User B's remaining 1 BTC for 4 GBP, even though the market price is in the range of 9 or 10 GBP/BTC.

Note that overall, User B gets 54 BTC for his 6 BTC, and so actually gets the price he was expecting to.  It's just that some was better than expected (5 sold to A for 10 GBP each) and some was much worse than expected (1 sold to C for 4 GBP).


This is how very high priced trades happen:

User A has 5 BTC and wants 45 GBP (selling 5 BTC at 9 GBP/BTC)
User B has 51 GBP and wants 5.1 BTC (buying 5.1 BTC at 10 GBP/BTC)

User A's order goes in first, and is unmatched.
User B's order goes in 2nd, and is partially matched at User A's rate of 9 GBP/BTC.
User B gives 45 GBP to user A and gets 5 BTC in exchange.
User B now has 6 GBP and the 'wants' value is updated to 0.1 BTC.

User C can now come along and sell 0.1 BTC to User B for 6 GBP, at a price of 60 GBP/BTC even though the market price is in the range of 9 or 10 GBP/BTC.

Note that overall, User B gets 5+0.1=5.1 BTC for his 45+6=51 GBP, and so actually gets the price he was expecting to.  It's just that some was better than expected (5 bought from A for 9 GBP each) and some was much worse than expected (0.1 bought from C for 60 GBP each).


This is why absurdly priced trades show up in the API - it's because they actually happen.

My patch to fix this and stop the silly priced trades is here:
  https://gitorious.org/intersango/intersango/merge_requests/3