<p>There is no way to determine (that I can imagine) the number of lost private keys, you would have to make a guess that after x years without movement the private key is lost but that would just be a guess.</p>

CC BY-SA 3.0
2013-04-18T03:57:44.587Z
Thus the notion of probabilistic measure. I'm certain with some modeling, we could develop a reasonable metric
Charles Hoskinson
CC BY-SA 3.0
2013-04-18T04:07:57.833Z
@CharlesHoskinson How? I can't imagine you could get any useful data on which to base a prediction.
Jeremy
CC BY-SA 3.0
2013-04-19T00:26:25.647Z
Take the set of all accounts and measure the transaction volume over a fixed period of time. Build a distribution and examine the outliers. Certain accounts will be high volume others no volume. Create a notion of average time within an account and if an account is several standard deviations outside the time range, then it is either a high frequency account or a dead account
Charles Hoskinson
CC BY-SA 3.0
2013-04-19T00:28:12.827Z
This analysis would also be useful for studying iceberging techniques for moving large chunks of bitcoins without having the market discover the divestment
Charles Hoskinson
CC BY-SA 3.0
2013-04-18T03:18:26.390Z
2013-04-18T03:18:26.390Z
stateless
<p>A digital currency with user-defined anonymity will cause any estimates to simply be guesstimates.    </p>

<p>There are other areas where studies have attempted to quantify something and simply have concluded there is no reliable way to come up with the number so rather than provide misinformation there simply is no estimate made.</p>

<p>Essentially you could give a rough guesstimate of the upper bound.  Any coin that hasn't moved in the past year, for instance, might go under the possibly lost for a year or more.  That data is available and reportable.   But who knows if the real level of coins that haven't moved for over a year is because they were lost or simply are being saved and not spent.  Maybe it is 98% saved and 2% lost.  Or not.  Who knows.</p>

CC BY-SA 3.0
2013-04-18T04:37:39.833Z
Yes and what do you think the distribution would be? Poisson?
Charles Hoskinson
CC BY-SA 3.0
2013-04-18T04:12:56.677Z
2013-04-18T04:12:56.677Z
Stephen Gornick
<p>I am building some new metrics to better understand the Bitcoin economy and one that seems to be useful is a probabilistic notion that a Bitcoin has been lost. I'm aware of the bitcoin days destroyed, but has anyone done any modeling to gain a sense if a Bitcoin has been destroyed as a result of a lost key or a transaction to a bad address?</p>

<bitcoin-economy><destroy-bitcoins>
Probablity that a Bitcoin has been Lost
Charles Hoskinson
# Probablity that a Bitcoin has been Lost

(Asked by: username_0 on 2013-04-18)

I am building some new metrics to better understand the Bitcoin economy and one that seems to be useful is a probabilistic notion that a Bitcoin has been lost. I'm aware of the bitcoin days destroyed, but has anyone done any modeling to gain a sense if a Bitcoin has been destroyed as a result of a lost key or a transaction to a bad address?

**Tags:** bitcoin-economy, destroy-bitcoins


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## 2 answers

### Answer by username_1 on 2013-04-18. Score: 5

There is no way to determine (that I can imagine) the number of lost private keys, you would have to make a guess that after x years without movement the private key is lost but that would just be a guess.

> **Comments:**
> **username_0**: Thus the notion of probabilistic measure. I'm certain with some modeling, we could develop a reasonable metric  
> **username_2**: @username_0 How? I can't imagine you could get any useful data on which to base a prediction.  
> **username_0**: Take the set of all accounts and measure the transaction volume over a fixed period of time. Build a distribution and examine the outliers. Certain accounts will be high volume others no volume. Create a notion of average time within an account and if an account is several standard deviations outside the time range, then it is either a high frequency account or a dead account  
> **username_0**: This analysis would also be useful for studying iceberging techniques for moving large chunks of bitcoins without having the market discover the divestment  

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### Answer by username_3 on 2013-04-18. Score: 1

A digital currency with user-defined anonymity will cause any estimates to simply be guesstimates.

There are other areas where studies have attempted to quantify something and simply have concluded there is no reliable way to come up with the number so rather than provide misinformation there simply is no estimate made.

Essentially you could give a rough guesstimate of the upper bound. Any coin that hasn't moved in the past year, for instance, might go under the possibly lost for a year or more. That data is available and reportable. But who knows if the real level of coins that haven't moved for over a year is because they were lost or simply are being saved and not spent. Maybe it is 98% saved and 2% lost. Or not. Who knows.

> **Comments:**
> **username_0**: Yes and what do you think the distribution would be? Poisson?  

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