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Using Benford’s Law to Detect Bitcoin Manipulation

statmodeling.stat.columbia.edu

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Re: Using Benford’s Law to Detect Bitcoin Manipulation

#81
post #22

Frankly, I can’t judge the merits of this article because I lack the knowledge required. But I think at this point we know that all cryptocurrencies are ‘greater fool’ “investments”. [1] They are in every way totally irrelevant and detrimental to society. Governments are unfortunately slow to crack down on the exchanges, although progress is being made. And that effort is essential to battle the cancer that is the ra…

I equally find it strange that people continue to come to hackernews- the Silicon Valley VC startup land - and can’t grasp that the infrastructure for programmable money might have some value. And write off p2p communication and coordination tools as zero-sum/ fraudulent games. And then wish for the government to ban other people’s jobs and hobby’s and communities because they don’t like it. Blows my mind that people…

> the infrastructure for programmable money might have some value

And it has, Central Banks are creating their own digital currencies for digital wallets. They aware based on real needs for speed, volume, security, trazability, etc.

> the infrastructure for programmable money might have some value

I think that people understand cryptocurrencies quite well, and from that knowledge comes the skepticism.

> wish for the government to ban other people’s jobs and hobby’s and communities because they don’t like it

I want it banned because people with unsofisticated knowledge of economics and technology are being scammed out of their money by snake oil salesmen. But, that is not needed. As soon as normal accounting guaratees are required it probably will call by its own weight.

I know people working hard jobs putting hard earned money into this scam trying too get money to better their lives. It breaks my heart to thing that they are being lied in such a way, this study suggests is all manipulation, and that is my experience with everything related to cryptocurrencies. The sooner it gets regulated the better.

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#82

Why do some people keep trying to prove Bitcoin as a pump and dump scheme? Yes it has pumps and dumps, but if you zoom out, those pumps and dumps get smoothed out and you see a digital asset which keeps increasing in value because people see it as a hedge against USD and other currencies inflation. The increase in value is not infinite, and that can also be seen in the price increase curve (log). The price increase i…

>Why do some people keep trying to prove Bitcoin as a pump and dump scheme?

And why do all the Bitcoin bros get instantly butthurt the moment anyone shows any skepticism about it (but they feel totally entitled to have skepticism about any/all other currencies)

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#83

Benfords law is used to find evidence that the numbers came from a person, not a measurement or mathematical process, right? So anyone who knows what a limit order is should not be surprised to find evidence that humans are involved in picking the prices, right? It should be obvious that violating Benfords law isn't evidence of fraud or manipulation or even fomo, just evidence that the price is impacted by the people…

[deleted]

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#84

I mean, we need only remember that in late 2016 two wash trading bots at Coinbase accounted for 99% of all global trading volume in Litecoin. (Likely Charlie Lee, btw) [1] And that Tether continues to exist after this devastating NYAG settlement. [2] It's clearly manipulated. And it's manipulated because its roughly speaking globally unregulated, and tracks globally via cross-exchange arbitrage bots. If the author fo…

Why is what tether did (held 76% of its reserves in cash and cash equivalents and other short-term deposits and commercial paper as of the end of March, as opposed to 100% backed) any different to fractional reserve banking?

The minuscule fine ($18M) shows that the AG didn't even really think it was a big deal.

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#85

Earlier quoted context omitted.

The time series spanning 3 orders of magnitude over a course if years is not sufficient condition for Benford's law to apply. As a trivial example, a stock whose price started at $1 and increased by $1 every day for 30 years would span 4 orders of magnitude over that time period, but would not follow Benford's law. A formal justification for applying Benford's law to a time series like that would depend on some kind…

> As a trivial example, a stock whose price started at $1 and increased by $1 every day for 30 years would span 4 orders of magnitude over that time period, but would not follow Benford's law. That's actually a great illustration of the kind of thing we'd expect Benford's Law to raise red flags about. Your hypothetical posits the kind of behavior that we would not expect to naturally come out of the kind of process t…

> So, if we saw the kinds of initial digits that your hypothetical produces, we would be correct to guess that this stock is behaving in an unusual way.

Sure

> And it would be a correct application of Benford's Law, because we can reasonably expect that its key assumptions apply.

No, absolutely not.

The fact that Benford's law would trigger on that one example is not evidence that using Benford's law in this situation is actually a reasonable thing to do. Applying Benford's law to observations over time from a highly correlated time series (e.g. a stock price over time) is fundamentally different from applying Benford's law to a bunch of observations from different time series at a single point in time (e.g. the NYSE prices in the first figure from the original post). As I pointed out in my comment above, applying Benford's law to the single time series must be justified by an ergodicity argument which nobody has attempted to make. I don't know if Smith has any background in stochastic processes, but given Gelman's work on MCMC convergence (which deals with similar issues) he should have flagged that.

> It turns out that red flags are useful even when they're not admissible in court, because they provide an easy heuristic that you can use to help direct your search for more compelling evidence.

No. A "red flag" like this with no theoretical justification and unknown operating characteristics is a good way to get led down false paths. About the only thing it's good for is confirmation bias.

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#86

Benfords law is used to find evidence that the numbers came from a person, not a measurement or mathematical process, right? So anyone who knows what a limit order is should not be surprised to find evidence that humans are involved in picking the prices, right? It should be obvious that violating Benfords law isn't evidence of fraud or manipulation or even fomo, just evidence that the price is impacted by the people…

Benfords law is a perfect example of something that is cool and compelling and then gets applied inappropriately all over the place by people who don’t know better. Voting, for example.

Usually because the pop-description is, as usual, misleading. People find data covering "several orders of magnitude" and just assume by some cosmic fact that Benford's law should apply, despite the mechanics being their data having no reason to imply that the law holds.

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#87

I mean, we need only remember that in late 2016 two wash trading bots at Coinbase accounted for 99% of all global trading volume in Litecoin. (Likely Charlie Lee, btw) [1] And that Tether continues to exist after this devastating NYAG settlement. [2] It's clearly manipulated. And it's manipulated because its roughly speaking globally unregulated, and tracks globally via cross-exchange arbitrage bots. If the author fo…

Why is what tether did (held 76% of its reserves in cash and cash equivalents and other short-term deposits and commercial paper as of the end of March, as opposed to 100% backed) any different to fractional reserve banking? The minuscule fine ($18M) shows that the AG didn't even really think it was a big deal.

Because Tether lied about it.

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#88
post #7

What is the statistical likelihood of this appearing by chance? Note that 2014 to today isn't actually that long of a timeframe, as prices in a time-series are highly linked to the previous data point. Berkshire Hathaway has been trading for several decades; so that's 40 years of data; as compared to 7 years of data. yet the author, by using the same charts, seems to falsely imply that these are remotely comparable.…

Like what does the graph look like for TSLA? Or GOOG?

TSLA: https://i.imgur.com/hZVaJG8.png

GOOG: https://i.imgur.com/Wz0am68.png

MSFT: https://i.imgur.com/gEYgIN3.png

N.B. these are split-adjusted.

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#89
post #9

Sorry for the shameless plug. I made a video about Benford's law a while ago for anybody wondering how we get these values https://www.youtube.com/watch?v=9hY43XpVr1I&ab_channel=Treen...

I suspect your "shameless plug" message is trying to draw attention away from the fact that you've added an adblock whitelisting query param to the url, presumably whitelisting ads from certain providers. This is more unethical than sharing tracking links in here.

[deleted]

Re: Using Benford’s Law to Detect Bitcoin Manipulation

#90

Earlier quoted context omitted.

Why is what tether did (held 76% of its reserves in cash and cash equivalents and other short-term deposits and commercial paper as of the end of March, as opposed to 100% backed) any different to fractional reserve banking? The minuscule fine ($18M) shows that the AG didn't even really think it was a big deal.

Because Tether lied about it.

Which is broadly referred to as fraud
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