
Empirical explanation for Craig Wright's selfish mining Bitcoin bet - grano
http://www.andygranowitz.com/2018/04/12/empirical-explanation-craig-wright-selfish-mining-bitcoin-bet.html
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munro
This makes me think of the classic Monty Hall problem, where Monty opens a
door and asks if you would like to switch or stay.. which is actually giving
you information that the door opened was a goat (which he had to do if you
picked the door with the other goat).

So when try to understand "how long until the block is mined?" at t=10, you're
given information that the block has not been mined yet and have to update
your predictions, thus making the average time from t=10 another 10 minutes
away.

The hard part I have internalizing is if I were to make a progress bar for
block mining, it would be totally useless because it'd always show 10 minutes
away, until BOOM it hits 100% when a block is found (or someone else does).

Then I had a realization that it's the wrong question to ask because the time
is truly unknown, but instead we could show a "progress" bar of the
percentile! So starts at 0.1%, then 5%, then 50% (median time whatever that
is). Thinking this way becomes very intuitive, because now you're no longer
wondering when it will finish, but instead are given a benchmark of survival
time and can think things like "crazy, only 1% of blocks have taken more than
40 minutes to mine." and at the same time get the piece of mind of seeing
something "progress" while at the same time being comfortable that it will
never finish, until it does.

~~~
madavidj
It's almost like a reverse Monty Hall problem.

In the Monty Hall, the extra bit of information seems useless, but is actually
useful. In a poisson process, the extra bit of information seems useful, but
is actually useless.

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CyberDildonics
Don't promote this guy, it should be obvious he is a conman. He claimed to be
the creator of bitcoin ten years ago using C++ and Qt, yet there is no other
software that he has written anywhere to be found.

He claimed he would sign a message with the private key from the genesis
block, yet never did. Instead he used a previously signed message to dupe
people.

Here is a blog post that he edited to make it look like he was working on
cryptocurrency in 2008:

[https://i.imgur.com/hAbPhW3.png](https://i.imgur.com/hAbPhW3.png)

Here is a compilation of evidence against his claims:

[https://www.reddit.com/r/btc/comments/89bui6/buterin_about_c...](https://www.reddit.com/r/btc/comments/89bui6/buterin_about_csw_why_is_this_fraud_allowed_to/dwq8egl/)

He made these claims to get funding for his company which is now on a tear to
patent everything they can:

[https://www.reuters.com/investigates/special-
report/bitcoin-...](https://www.reuters.com/investigates/special-
report/bitcoin-wright-patents/)

His selfish mining paper was also found to have large parts plagiarized from
previous papers published in the 90s.

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tromp
Closely related, [1] previously discussed the paradoxical fact that:

If you pick a random point in time, you expect 20 minutes between the previous
block and the next block on average.

[1]
[https://news.ycombinator.com/item?id=16469382](https://news.ycombinator.com/item?id=16469382)

~~~
usmannk
Not quite. The paradoxical fact is that if you pick a random point in time,
it’s expected that there is 20 minutes between that point and the next block.
Even if there’s already been 20 minutes since the previous block!

Edit: woops! See below.

~~~
tgb
The original poster had it right - you are mistakenly thinking that the block
time is 20 minutes when it's 10. Once you make that correction, you are both
correct.

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KirinDave
I knew Wright was shady, but did he seriously bet that an exponential
distribution doesn't have the properties it is known to have?

Cuz, uh, wow.

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oh_sigh
Wright getting simple math(relative to the math in Bitcoin) wrong is even more
evidence that he is not Satoshi - not that anyone particularly needed more
evidence

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barbegal
Craig Wright would be correct if not for the information that the dishonest
miners found the "next" block. If anyone could have found the next block and
the dishonest miners simply found a block at t=0 then the expected time for
the honest miners to find a block would be at t=5 minutes.

~~~
__blockcipher__
Nope, this is totally wrong.

To put it bluntly, please stop spreading this garbage. CSW completely
misunderstood memorylessness (which, just to state the obvious, is solid
bayesian evidence that he is not Satoshi).

Regardless of the knowledge of the participants, it will always take an EV of
10 minutes when alpha = 1, or an EV = 15 given alpha = 2/3 in this example.

~~~
barbegal
I completely agree but in this formulation of the problem the honest miners
started at t=-10 so may have found the block before the dishonest miners in
the timeframe from t=-10 to t=0.

~~~
__blockcipher__
They did not, that is (perhaps implicitly) part of the problem description. It
never says the honest miner finds block N, it asks when they are expected to
implying it hadn't happen up to that point. Also, the dishonest miner found
the "next block" but did not broadcast it at t=0, which is essentially
irrelevant information because it doesn't matter whether the honest miners
know about the hidden block or not, either way it will take them an EV of 15
minutes at any given point in time regardless of knowledge

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908087
Something I've rarely seen asked in regards to the "Bitcoin will become the
main global currency" fever dream fantasy is this:

Who would want to live in a world where a new multi-trillionaire class is
created out of thin air, particularly given the shady history of many who
would be among those people? What blows my mind is that the people I see
hoping for this are often the same ones claiming Bitcoin will _improve_ global
wealth inequality.

If you think high wealth individuals have too much control and too little
accountability now, just think about what would happen if people who hoarded
Bitcoin drug profits and people like Brock Pierce suddenly held hundreds of
billions of dollars or more, all of which was liquid.

~~~
bdcravens
Not really sure how this comment relates to the submitted article. This feels
more like

    
    
        if (HN_title.contains('Bitcoin')) {
            express_generic_opinion();
        }

