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Topic: [CHART] Bitcoin Actual Transaction Volume? (using "change is never last" bug) (Read 1936 times)

donator
Activity: 668
Merit: 500
As I mentioned in the opposite thread, since the emergence of alternative clients you can't take these numbers as good.  Electrum until last week always sent the change as the last output, so you'll be misinterpreting over one-year's worth of Electrum transactions.
donator
Activity: 2772
Merit: 1019
Also, this could be compared to market cap to find out whether BTC is currently over or under valued compared to prior dates, could it not?  I think that'd be a neat analysis.  Smiley  In fact, we can at least easily compare the two charts.

I'm not sure...

firstly: think about what you see when you remove the exchange rate from both charts (they have it in common, right?)

secondly: bitcoins value only stems from its transactional features in part. In fact I think the majority of it's value is rooted in its store-of-wealth features. So you can't judge wether or not bitcoin is over-/undervalued just by looking at transaction volume. It surely plays its part because it indicates usage and increase in usage definitely results in increase of bitcoins value.

Could you calculate the average ratio between change and transaction output? Or better yet, chart this ratio? That would be insanely useful.

would you want me to calculate the ratio per transaction and then average that ("avg(output0/output1)") or add up the outputs per day and take that ratio ("sum(output0)/sum(output1)") ?

If the latter, you can kind of see that ratio in my first chart (yellow vs. red)
legendary
Activity: 1246
Merit: 1077
Also, this could be compared to market cap to find out whether BTC is currently over or under valued compared to prior dates, could it not?  I think that'd be a neat analysis.  Smiley  In fact, we can at least easily compare the two charts.

I'm not sure...

firstly: think about what you see when you remove the exchange rate from both charts (they have it in common, right?)

secondly: bitcoins value only stems from its transactional features in part. In fact I think the majority of it's value is rooted in its store-of-wealth features. So you can't judge wether or not bitcoin is over-/undervalued just by looking at transaction volume. It surely plays its part because it indicates usage and increase in usage definitely results in increase of bitcoins value.

Could you calculate the average ratio between change and transaction output? Or better yet, chart this ratio? That would be insanely useful.
donator
Activity: 2772
Merit: 1019
Also, this could be compared to market cap to find out whether BTC is currently over or under valued compared to prior dates, could it not?  I think that'd be a neat analysis.  Smiley  In fact, we can at least easily compare the two charts.

I'm not sure...

firstly: think about what you see when you remove the exchange rate from both charts (they have it in common, right?)

secondly: bitcoins value only stems from its transactional features in part. In fact I think the majority of it's value is rooted in its store-of-wealth features. So you can't judge wether or not bitcoin is over-/undervalued just by looking at transaction volume. It surely plays its part because it indicates usage and increase in usage definitely results in increase of bitcoins value.
donator
Activity: 2772
Merit: 1019
This really showcases definite growth of BTC.  Even though the bug is now fixed, the correlation between transaction volume and USD volume can likely be used for a decent while into the future to continue calculating close-to-actual USD transaction volume.  Anyone want to calculate a regression between the two?  Molecular, are you willing to share the spreadsheet of data?  I am curious what the r-squared value is.

sure. http://pastebin.com/jBmECtVS
legendary
Activity: 1400
Merit: 1005
This really showcases definite growth of BTC.  Even though the bug is now fixed, the correlation between transaction volume and USD volume can likely be used for a decent while into the future to continue calculating close-to-actual USD transaction volume.  Anyone want to calculate a regression between the two?  Molecular, are you willing to share the spreadsheet of data?  I am curious what the r-squared value is.

Also, this could be compared to market cap to find out whether BTC is currently over or under valued compared to prior dates, could it not?  I think that'd be a neat analysis.  Smiley  In fact, we can at least easily compare the two charts.



donator
Activity: 2772
Merit: 1019
or we are really moving a shitload of money nowadays (maybe both).

Eyeballing this, it roughly correlates to an increased number of transactions as well. 

I would be curious to know if the average for output #1 is increasing much though.

What average do you mean? You can see the average per day in the chart. Maybe you're talking about the average per transaction?
legendary
Activity: 2506
Merit: 1010
or we are really moving a shitload of money nowadays (maybe both).

Eyeballing this, it roughly correlates to an increased number of transactions as well. 

I would be curious to know if the average for output #1 is increasing much though.
sr. member
Activity: 252
Merit: 250
Thx for the picture. Kudos for running this against MTG trading data. I'll take some time to look further in to this.

I am curious if this 'little' bug has been exploited in some way we can't even think of. For data mining, tracing... We'll see.
legendary
Activity: 2156
Merit: 1072
Crypto is the separation of Power and State.
Nice work, pretty charts!

donator
Activity: 2772
Merit: 1019
I joined mtgox trade data and made a daily (previous charts are weekly) chart of output #1 transaction volume in USD (by multiplying the output #1 transaction volume in BTC with the respective days volume-weighted mtGoxUSD rate):



Now either the assumptions don't hold to the extent I'm wishing for (for example more prevalent use of alternative clients without the bug) or we are really moving a shitload of money nowadays (maybe both).
donator
Activity: 2772
Merit: 1019
Just a small note:
I introduced that bug with the 'sendmany' command two years ago (commit b9d1ed85).

So you should exclude data which is older than the day this bug were widespread. Not much difference, thought.

Good point, thanks. Not much data to be seen in 2009 anyway, though.
sr. member
Activity: 477
Merit: 500
Just a small note:
I introduced that bug with the 'sendmany' command two years ago (commit b9d1ed85).

So you should exclude data which is older than the day this bug were widespread. Not much difference, thought.
donator
Activity: 2772
Merit: 1019
As discovered not long ago there was/is a bug in the Satoshi client: https://bitcointalksearch.org/topic/m.1398752

In a nutshell it means that the change output of a transaction is never the last output (outputs are ordered). For transactions with 2 output this means that output #0 is the change and output #1 is the actual amount sent.

As we can see here, transactions with exactly 2 outputs make up the majority of both number and volume of transactions:

(click images for slightly larger version)



So let's look at the volume by output index:



We can clearly see the supposed change output (output #0, yellow) is a lot larger than the supposed actual amount output (output #1, red). Outputs with index higher than 2 (blue) have relatively low volume.

So now under the assumption that most transactions are 2-output transaction generated by the satoshi client we can look at only the volume of output #1 and hope to see a good approximation of Bitcoins actual transaction volume:



EDIT: queries used: http://pastebin.com/Mg1FdEts

Any ideas how correct this might or might not be, how big the error could be, how to estimate it or any other comments on this?
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