Abstract. This paper analyzes the supply and demand for Bitcoinbased Ponzi schemes. There are a variety of these types of scams: from long cons such as Bitcoin Savings & Trust to overnight doubling schemes that do not take off. We investigate what makes some Ponzi schemes successful and others less so. By scouring 11 424 threads on bitcointalk.org, we identify 1 780 distinct scams. Of these, half lasted a week or less.
Using survival analysis, we identify factors that affect scam persistence. One approach that appears to elongate the life of the scam is when the scammer interacts a lot with their victims, such as by posting more than a quarter of the comments in the related thread. By contrast, we also find that scams are shorter-lived when the scammers register their account on the same day that they post about their scam. Surprisingly, more daily posts by victims is associated with the scam ending sooner.
The Risks and Rewards of Trading CryptocurrenciesJordan Berger
In this e-book, we share with you everything from the basics of what cryptocurrencies are and how to open an account to the strategies for charting their directions and ways to protect yourself from a range of risks.
By the end of this e-book, you’ll certainly know more about cryptocurrency
than most people out there.For this first chapter, we will be covering 5 topics:
1. What Is Cryptocurrency?
2. How DoCryptocurrencies Work?
3. How Are The Cryptocurrencies Value Determined?
4. What Is Cryptocurrency Used For?
5. Why Cryptocurrency?
This is one of the most frequently asked questions out there. What is cryptocurrency? To make it simple, cryptocurrency is a digital version of money where the transactions are done online. A cryptocurrency is a medium of exchange just like your normal everyday currency such as the USD, but designed for the purpose of exchanging digital information through a process known as cryptography.
The first ever-successful cryptocurrency emerged from the invention of Bitcoin, by Satoshi Nakamoto. This was then followed by the birth of other types of crytocurrencies competing against Bitcoin.
Discussion Personal and Professional Social Work ValuesHetero.docxduketjoy27252
Discussion: Personal and Professional Social Work Values
Heterosexism is defined as "the discrimination or prejudice by heterosexuals against homosexuals" (merriam-webster.com) and is predicated on the belief that being heterosexual is the norm and the only accepted type of relationship.
Everyday heterosexism is exemplified in our media, our policies, and daily practices. By making these assumptions, social workers can be in part culpable for the oppression and marginalization experienced by the LGBTQ community.
As a profession, social work embraces diversity and strives to ensure equal rights for all. The National Association of Social Workers (NASW) is committed to supporting the needs of these groups and, in turn, they created the National Committee on Gay, Lesbian, Bisexual and Transgender Issues. During this week's discussion, you will be asked to consider how one's own personal views on sexual orientation may clash with the profession's stance.
Post a scenario of how a social worker's personal, ethical, and moral values in relation to the LGBTQ community might conflict with those of their clients. Explain the distinction between personal ethics and values and professional ethics and values evident in the social work profession in addressing this community. Be specific and explain how this distinction relates to the scenario you posted. Also, explain how prejudice and bias might create barriers to fulfilling your professional responsibility to the LGBTQ community.
References:
Adams, M., Blumenfeld, W. J., Castaneda, C., Catalano, D. C. J., DeJong, K., Hackman, H. W,... Zuniga, X. (Eds.). (2018). Readings for diversity and social justice (4th ed.). New York, NY: Routledge Press.
· Chapter 73, The interSEXion: queer progressive agenda (pp. 391-394)
· Chapter 66, Privilege (pp. 367-370)
· Chapter 69, Women & LGBT people under attack: 1903s and now (pp. 378-381)
· Chapter 85, Mestiza/o gender: Notes toward transformative masculinity (pp. 434-439)
· Chapter 72, Introduction-How sex changed: A history of transsexuality (pp. 388-390)
· Chapter 76, Transgender liberation (pp. 400-403)
· Chapter 81, Mutilating gender (pp. 419-425)
· Chapter 83, Trans woman manifesto (pp. 429-432)
· Chapter 77, The Impact of juvenile court on Queer and trans/gender non-conforming youth (pp. 403-406)
Running head: Bitcoin as a cryptocurrency 1
Bitcoin as a cryptocurrency 8Bitcoin as a Cryptocurrency of Misconduct
Roger F. Lewis
Miami Dade College-North Campus
June 5, 2019
Bitcoin as a Cryptocurrency of Misconduct
In the expansion of cryptocurrencies in particular bitcoins have resulted in providing clients with exceptional advantages, the advantages in this matter have not had their hazards and struggles. In the peculiar free mode in the cryptocurrency arcade, it has been in constant misuse and linked to several illegal activities. Lawmakers globally repetitively stumble upon this very position (Anon,2019). The tendency on allowing a market to settle on i.
The Risks and Rewards of Trading CryptocurrenciesJordan Berger
In this e-book, we share with you everything from the basics of what cryptocurrencies are and how to open an account to the strategies for charting their directions and ways to protect yourself from a range of risks.
By the end of this e-book, you’ll certainly know more about cryptocurrency
than most people out there.For this first chapter, we will be covering 5 topics:
1. What Is Cryptocurrency?
2. How DoCryptocurrencies Work?
3. How Are The Cryptocurrencies Value Determined?
4. What Is Cryptocurrency Used For?
5. Why Cryptocurrency?
This is one of the most frequently asked questions out there. What is cryptocurrency? To make it simple, cryptocurrency is a digital version of money where the transactions are done online. A cryptocurrency is a medium of exchange just like your normal everyday currency such as the USD, but designed for the purpose of exchanging digital information through a process known as cryptography.
The first ever-successful cryptocurrency emerged from the invention of Bitcoin, by Satoshi Nakamoto. This was then followed by the birth of other types of crytocurrencies competing against Bitcoin.
Discussion Personal and Professional Social Work ValuesHetero.docxduketjoy27252
Discussion: Personal and Professional Social Work Values
Heterosexism is defined as "the discrimination or prejudice by heterosexuals against homosexuals" (merriam-webster.com) and is predicated on the belief that being heterosexual is the norm and the only accepted type of relationship.
Everyday heterosexism is exemplified in our media, our policies, and daily practices. By making these assumptions, social workers can be in part culpable for the oppression and marginalization experienced by the LGBTQ community.
As a profession, social work embraces diversity and strives to ensure equal rights for all. The National Association of Social Workers (NASW) is committed to supporting the needs of these groups and, in turn, they created the National Committee on Gay, Lesbian, Bisexual and Transgender Issues. During this week's discussion, you will be asked to consider how one's own personal views on sexual orientation may clash with the profession's stance.
Post a scenario of how a social worker's personal, ethical, and moral values in relation to the LGBTQ community might conflict with those of their clients. Explain the distinction between personal ethics and values and professional ethics and values evident in the social work profession in addressing this community. Be specific and explain how this distinction relates to the scenario you posted. Also, explain how prejudice and bias might create barriers to fulfilling your professional responsibility to the LGBTQ community.
References:
Adams, M., Blumenfeld, W. J., Castaneda, C., Catalano, D. C. J., DeJong, K., Hackman, H. W,... Zuniga, X. (Eds.). (2018). Readings for diversity and social justice (4th ed.). New York, NY: Routledge Press.
· Chapter 73, The interSEXion: queer progressive agenda (pp. 391-394)
· Chapter 66, Privilege (pp. 367-370)
· Chapter 69, Women & LGBT people under attack: 1903s and now (pp. 378-381)
· Chapter 85, Mestiza/o gender: Notes toward transformative masculinity (pp. 434-439)
· Chapter 72, Introduction-How sex changed: A history of transsexuality (pp. 388-390)
· Chapter 76, Transgender liberation (pp. 400-403)
· Chapter 81, Mutilating gender (pp. 419-425)
· Chapter 83, Trans woman manifesto (pp. 429-432)
· Chapter 77, The Impact of juvenile court on Queer and trans/gender non-conforming youth (pp. 403-406)
Running head: Bitcoin as a cryptocurrency 1
Bitcoin as a cryptocurrency 8Bitcoin as a Cryptocurrency of Misconduct
Roger F. Lewis
Miami Dade College-North Campus
June 5, 2019
Bitcoin as a Cryptocurrency of Misconduct
In the expansion of cryptocurrencies in particular bitcoins have resulted in providing clients with exceptional advantages, the advantages in this matter have not had their hazards and struggles. In the peculiar free mode in the cryptocurrency arcade, it has been in constant misuse and linked to several illegal activities. Lawmakers globally repetitively stumble upon this very position (Anon,2019). The tendency on allowing a market to settle on i.
Bitter to Better — How to Make Bitcoin a Better Currency.Qutomatic
Bitter to Better — How to Make Bitcoin a Better Currency.
Bitcoin is a distributed digital currency which has attracted a substantial number of users. We perform an in-depth investigation to understand what
made Bitcoin so successful, while decades of research on cryptographic e-cash
has not lead to a large-scale deployment. We ask also how Bitcoin could become
a good candidate for a long-lived stable currency. In doing so, we identify several
issues and attacks of Bitcoin, and propose suitable techniques to address them
CELSIUS NETWORK is a decentralized lending platform that leverages over-the-counter (OTC) trading and machine learning to enable secure, peer-to-peer borrowing for the crypto market. It has brought together a platform where lenders can leverage their funds to earn up to 5% per month and borrowers can access funds at a significantly lower interest rate than from traditional banks.
SEE URL's: https://bizvestor.com.ng/reviews/celsius-network-crypto-investment/
1-0 – What Is Cryptocurrency?
What is cryptocurrency? I’m sure many of you are curious of this so called
“21st
-century money of the future and due to its increasing recognition and
security, the cryptocurrency market looks bright ahead.
By the end of this e-book, you’ll certainly know more about cryptocurrency
than most people out there.For this first chapter, we will be covering 5 topics:
How to Make Bitcoin a Better Currency.
Bitcoin is a distributed digital currency which has attracted a substantial number of users. We perform an in-depth investigation to understand what
made Bitcoin so successful, while decades of research on cryptographic e-cash
has not lead to a large-scale deployment. We ask also how Bitcoin could become
a good candidate for a long-lived stable currency. In doing so, we identify several
issues and attacks of Bitcoin, and propose suitable techniques to address them
Unless you’ve been living under a rock you will have heard about cryptocurrencies (cryptos). The most famous of these is Bitcoin which is always in the news. Some people think that cryptocurrencies are a scam, but they are not. If you know what you’re doing you can make a tidy fortune with them.
Some people are too scared to get involved with cryptocurrencies. They do not understand them and all. Instead, what they focus on are the scams that hit the headlines daily. Unfortunately, scams exist everywhere, even in fiat currencies, and cryptocurrencies are no exception.
Fortunately, unlike fiat currencies, cryptocurrencies are secured by Blockchain, the technology on which cryptocurrencies are developed, and are almost impossible to interfere with.
However, by not getting involved in cryptocurrency, you’re losing out big time. Cryptocurrency is the economic future of the online world. Based on the formidable Blockchain technology, the first cryptocurrency, Bitcoin, has already reached an all-time high in November, 2021. That means if you had just one Bitcoin that you bought at the start of 2009, you would be $68,000 richer by November 2021.
Now, other cryptocurrencies are where Bitcoin was in 2009, and you have the same opportunity the same person had in 2009.
The Ultimate Guide to Understanding Cryptocurrency: Invest with ConfidenceKhemitEric
What is cryptocurrency? I’m sure many of you are curious of this so called
“21st-century money of the future and due to its increasing recognition and
security, the cryptocurrency market looks bright ahead.
By the end of this e-book, you’ll certainly know more about cryptocurrency
than most people out there.For this first chapter, we will be covering 5 topics:
1. What Is Cryptocurrency?
2. How DoCryptocurrencies Work?
3. How Are The Cryptocurrencies Value Determined?
4. What Is Cryptocurrency Used For?
5. Why Cryptocurrency?
Discover the Secrets to Making a Fortune with CryptocurrencyKhemitEric
What is cryptocurrency? I’m sure many of you are curious of this so called
“21st-century money of the future and due to its increasing recognition and
security, the cryptocurrency market looks bright ahead.
By the end of this e-book, you’ll certainly know more about cryptocurrency
than most people out there.For this first chapter, we will be covering 5 topics:
1. What Is Cryptocurrency?
2. How DoCryptocurrencies Work?
3. How Are The Cryptocurrencies Value Determined?
4. What Is Cryptocurrency Used For?
5. Why Cryptocurrency?
What Is Cryptocurrency?
This is the first process of launching a new crypto currency in this world. The ICO is like IPO. This makes the crypto currency its legal existence and essential for its survival.
Best and easy tips to mining bitcoin.
Get Rich With Bitcoin Even If
You Have No Clue About Technology
The surprising wealth-building secret of a
globe-trotting vagabond.
Bullshiters - Who Are They And What Do We Know About Their LivesTrading Game Pty Ltd
‘Bullshitters’ are individuals who claim knowledge or expertise in an area where they
actually have little experience or skill. Despite this being a well-known and widespread
social phenomenon, relatively few large-scale empirical studies have been conducted into
this issue. This paper attempts to fill this gap in the literature by examining teenagers’
propensity to claim expertise in three mathematics constructs that do not really exist.
Using Programme for International Student Assessment (PISA) data from nine Anglophone
countries and over 40,000 young people, we find substantial differences in young people’s
tendency to bullshit across countries, genders and socio-economic groups. Bullshitters are
also found to exhibit high levels of overconfidence and believe they work hard, persevere
at tasks, and are popular amongst their peers. Together this provides important new insight
into who bullshitters are and the type of survey responses that they provide.
More Related Content
Similar to Analyzing the Bitcoin Ponzi Scheme Ecosystem
Bitter to Better — How to Make Bitcoin a Better Currency.Qutomatic
Bitter to Better — How to Make Bitcoin a Better Currency.
Bitcoin is a distributed digital currency which has attracted a substantial number of users. We perform an in-depth investigation to understand what
made Bitcoin so successful, while decades of research on cryptographic e-cash
has not lead to a large-scale deployment. We ask also how Bitcoin could become
a good candidate for a long-lived stable currency. In doing so, we identify several
issues and attacks of Bitcoin, and propose suitable techniques to address them
CELSIUS NETWORK is a decentralized lending platform that leverages over-the-counter (OTC) trading and machine learning to enable secure, peer-to-peer borrowing for the crypto market. It has brought together a platform where lenders can leverage their funds to earn up to 5% per month and borrowers can access funds at a significantly lower interest rate than from traditional banks.
SEE URL's: https://bizvestor.com.ng/reviews/celsius-network-crypto-investment/
1-0 – What Is Cryptocurrency?
What is cryptocurrency? I’m sure many of you are curious of this so called
“21st
-century money of the future and due to its increasing recognition and
security, the cryptocurrency market looks bright ahead.
By the end of this e-book, you’ll certainly know more about cryptocurrency
than most people out there.For this first chapter, we will be covering 5 topics:
How to Make Bitcoin a Better Currency.
Bitcoin is a distributed digital currency which has attracted a substantial number of users. We perform an in-depth investigation to understand what
made Bitcoin so successful, while decades of research on cryptographic e-cash
has not lead to a large-scale deployment. We ask also how Bitcoin could become
a good candidate for a long-lived stable currency. In doing so, we identify several
issues and attacks of Bitcoin, and propose suitable techniques to address them
Unless you’ve been living under a rock you will have heard about cryptocurrencies (cryptos). The most famous of these is Bitcoin which is always in the news. Some people think that cryptocurrencies are a scam, but they are not. If you know what you’re doing you can make a tidy fortune with them.
Some people are too scared to get involved with cryptocurrencies. They do not understand them and all. Instead, what they focus on are the scams that hit the headlines daily. Unfortunately, scams exist everywhere, even in fiat currencies, and cryptocurrencies are no exception.
Fortunately, unlike fiat currencies, cryptocurrencies are secured by Blockchain, the technology on which cryptocurrencies are developed, and are almost impossible to interfere with.
However, by not getting involved in cryptocurrency, you’re losing out big time. Cryptocurrency is the economic future of the online world. Based on the formidable Blockchain technology, the first cryptocurrency, Bitcoin, has already reached an all-time high in November, 2021. That means if you had just one Bitcoin that you bought at the start of 2009, you would be $68,000 richer by November 2021.
Now, other cryptocurrencies are where Bitcoin was in 2009, and you have the same opportunity the same person had in 2009.
The Ultimate Guide to Understanding Cryptocurrency: Invest with ConfidenceKhemitEric
What is cryptocurrency? I’m sure many of you are curious of this so called
“21st-century money of the future and due to its increasing recognition and
security, the cryptocurrency market looks bright ahead.
By the end of this e-book, you’ll certainly know more about cryptocurrency
than most people out there.For this first chapter, we will be covering 5 topics:
1. What Is Cryptocurrency?
2. How DoCryptocurrencies Work?
3. How Are The Cryptocurrencies Value Determined?
4. What Is Cryptocurrency Used For?
5. Why Cryptocurrency?
Discover the Secrets to Making a Fortune with CryptocurrencyKhemitEric
What is cryptocurrency? I’m sure many of you are curious of this so called
“21st-century money of the future and due to its increasing recognition and
security, the cryptocurrency market looks bright ahead.
By the end of this e-book, you’ll certainly know more about cryptocurrency
than most people out there.For this first chapter, we will be covering 5 topics:
1. What Is Cryptocurrency?
2. How DoCryptocurrencies Work?
3. How Are The Cryptocurrencies Value Determined?
4. What Is Cryptocurrency Used For?
5. Why Cryptocurrency?
What Is Cryptocurrency?
This is the first process of launching a new crypto currency in this world. The ICO is like IPO. This makes the crypto currency its legal existence and essential for its survival.
Best and easy tips to mining bitcoin.
Get Rich With Bitcoin Even If
You Have No Clue About Technology
The surprising wealth-building secret of a
globe-trotting vagabond.
Bullshiters - Who Are They And What Do We Know About Their LivesTrading Game Pty Ltd
‘Bullshitters’ are individuals who claim knowledge or expertise in an area where they
actually have little experience or skill. Despite this being a well-known and widespread
social phenomenon, relatively few large-scale empirical studies have been conducted into
this issue. This paper attempts to fill this gap in the literature by examining teenagers’
propensity to claim expertise in three mathematics constructs that do not really exist.
Using Programme for International Student Assessment (PISA) data from nine Anglophone
countries and over 40,000 young people, we find substantial differences in young people’s
tendency to bullshit across countries, genders and socio-economic groups. Bullshitters are
also found to exhibit high levels of overconfidence and believe they work hard, persevere
at tasks, and are popular amongst their peers. Together this provides important new insight
into who bullshitters are and the type of survey responses that they provide.
Age-Related Physiological Changes and Their Clinical SignificanceTrading Game Pty Ltd
Physiological changes occur with aging in all organ systems. The cardiac output decreases, blood pressure increases and arteriosclerosis develops. The lungs show impaired gas exchange, a decrease in vital capacity and slower
expiratory flow rates. The creatinine clearance decreases with age although the serum creatinine level remains relatively constant due to a proportionate age-related decrease in creatinine production. Functional'changes, largely
related to altered motility patterns, occur in the gastrointestinal system with senescence, and atrophic gastritis and altered hepatic drug metabolism are common in the elderly. Progressive elevation of blood glucose occurs with age on a multifactorial basis and osteoporosis is frequently seen due 'to a linear
decline in bone mass after the fourth decade. The epidermis of the skin atrophies with age and due to changes in collagen and elastin the skin loses its tone and elasticity. Lean body mass declines with ag'e and this is primarily due to loss and atrophy of muscle cells. Degenerative changes occur in many
joints and this, combined with the loss of muscle mass, inhibits elderly patients locomotion. These changes with age have important practical implications for the clinical management of elderly patients: metabolism is altered, changes
in response to commonly used drugs make different drug dosages necessary and there is need for rational preventive programs of diet and exercise in an effort to delay or reverse some of these changes.
I provide a (very) brief introduction to game theory. I have developed these notes to
provide quick access to some of the basics of game theory; mainly as an aid for students
in courses in which I assumed familiarity with game theory but did not require it as a
prerequisite
The paper opens with an overview of the
commodity trading advisor (CTA) sector, highlighting the
significant growth that has taken place in the managed
futures industry in recent years and explaining how
the managed futures strategies that CTAs employ
work in practice. The breadth of sub-strategies under
the managed futures umbrella are then examined.
The third part of the paper examines the benefits and
perceived risks to investors of allocating to managed
futures strategies and also addresses various common
misunderstandings about CTAs.
The paper concludes by exploring the common ways
as to how investors can access the various investment
strategies that are available
Investor behaviour often deviates from logic and reason, and investors display many behaviour biases that influence their investment decision-making processes. The authors describe some common behavioural biases and suggest how to mitigate them.
This article is the antidote to news. It is long, and you probably won’t be able to skim it. Thanks to heavy news consumption, many people have lost the reading habit and struggle to absorb more than four pages straight.
This article will show you how to get out of this trap – if you are not already too deeply in it.
The Psychology and Neuroscience of Financial Decision MakingTrading Game Pty Ltd
Financial decisions are among the most important life-shaping decisions that people make. We review facts about financial decisions and what cognitive and neural processes influence them. Because of cognitive constraints and a low average level of financial literacy, many household decisions violate sound
financial principles. Households typically have underdiversified stock holdings and low retirement savings rates. Investors overextrapolate from past returns and trade too often. Even top corporate managers, who are typically highly educated, make decisions that are affected by overconfidence and personal history. Many of these behaviors can be explained by well-known principles from cognitive science.
A boom in high-quality accumulated evidence–especially how practical, low-cost ‘nudges’ can improve financial decisions–is
already giving clear guidance for balanced government regulation
Four different tests of 63 people found that those who kept their intentions private were more likely to achieve them than those who made them public and were acknowledged by others.
Once you've told people of your intentions, it gives you a “premature sense of completeness.”
You have “identity symbols” in your brain that make your self-image. Since both actions and talk create symbols in your brain, talking satisfies the brain enough that it “neglects the pursuit of further symbols.”
Why Inexperienced Investors Do Not Learn: They Do Not Know Their Past Portfol...Trading Game Pty Ltd
Recently, researchers have gone a step further from just documenting biases of individual investors.
More and more studies analyze how experience affects decisions and whether biases are eliminated
by trading experience and learning. A necessary condition to learn is that investors actually know
what happened in the past and that the views of the past are not biased. We contribute to the
above mentioned literature by showing why learning and experience go hand in hand. Inexperienced
investors are not able to give a reasonable self-assessment of their own past realized stock portfolio
performance which impedes investors’ learning ability. Based on the answers of 215 online broker
investors to an internet questionnaire, we analyze whether investors are able to correctly estimate
their own realized stock portfolio performance. We show that investors are hardly able to give a correct
estimate of their own past realized stock portfolio performance and that experienced investors are
better able to do so. In general, we can conclude that we find evidence that investor experience
lessens the simple mathematical error of estimating portfolio returns, but seems not to influence their
“behavioral” mistakes pertaining to how good (in absolute sense or relative to other investors) they
are.
ARE CEOS PAID FOR PERFORMANCE? Evaluating the Effectiveness of Equity IncentivesTrading Game Pty Ltd
Companies that awarded their Chief Executive Officers (CEOs) higher equity incentives had
below-median returns based on a sample of 429 large-cap U.S. companies observed from
2006 to 2015. On a 10-year cumulative basis, total shareholder returns of those companies
whose total summary pay (the level that must be disclosed in the summary tables of proxy
statements) was below their sector median outperformed those companies where pay
exceeded the sector median by as much as 39%.1
We show that a one-off incentive to bias advice has a persistent effect on advisers’ own actions and their future recommendations. In an experiment, advisers obtained information about a set of three differently risky investment options to advise less informed clients. The riskiest option was designed such that it is only preferred by risk-seeking individuals. When advisers are offered a bonus for recommending this option, half of them recommend it. In
contrast, in a control group without the bonus only four percent recommend it. After the bonus was removed, its effect remained.
In a second recommendation for the same options but without a bonus, those advisers who had previously faced it are almost six times more likely to recommend the riskiest option compared to the control group. A similar increase is found when advisers make the same choice for themselves. To explain our results we provide a theory based on advisers trying to uphold a positive self-image of being incorruptible. Maintaining a positive self-image then forces them to be consistent in the advice they give, even if it is biased
Gender equality has made great strides in the past 50 years.
It is no longer acceptable to restrict women’s access to
education or employment opportunities. The principle that
female talent, ambition and thinking should be rewarded
has taken root in most walks of life, even if full parity with
men is a distant prospect.
Yet in fund management the march to equality may be
long. Women make up only one in ten of the individuals
employed to look after investors’ money. Just 7% of the funds
sold to the public around the world are run by a woman.
Fund management groups are striving to increase their
recruitment of women, which bodes well for the future.
Yet, as Katharine Dixon, head of research at Citywire, and
Helena Morrissey, chief executive of Newton Investment
Management, both comment here, our loss today is the
absence of the skilled women fund managers who never
made it through.
There is a positive message from our report, however. For
the first time we show not only where women fund managers
are working, we also highlight those delivering ‘alpha’ returns
that could be the envy of some of their male colleagues.
Behavioural Finance - An Introspection Of Investor PsychologyTrading Game Pty Ltd
Investors always try to make rational decision while analyzing and interpreting information collected from various sources for different investment avenues to arrive at an optimal investment decision. But at the same time they are influenced by various psychological factors that influence them internally and bias their investment decision. Linter (1998) studied the various factors that influence internally the informed investment decision and included them under the discipline of behavioural finance. Behavioural finance studies how people make investment decision and influenced by internal factors and bias. The main purpose of the paper is to assess impact of behavioural factors over mutual fund investment decision made by investors in Raipur city.
The science of cycology: Failures to understand how everyday objects workTrading Game Pty Ltd
When their understanding of the basics of bicycle design was assessed objectively, people were
found to make frequent and serious mistakes, such as believing that the chain went around the front
wheel as well as the back wheel. Errors were reduced but not eliminated for bicycle experts, for men
more than women, and for people who were shown a real bicycle as they were tested. The results
demonstrate that most people’s conceptual understanding of this familiar, everyday object is sketchy
and shallow, even for information that is frequently encountered and easily perceived. This evidence
of a minimal and even inaccurate causal understanding is inconsistent with that of strong versions of
explanation-based (or theory-based) theories of categorization.
The SPIVA Australia Scorecard reports on the performance of actively managed Australian mutual funds against their respective benchmark indices over one-, three-, and five-year investment horizons. In this scorecard, we evaluated returns of more than 620 Australian equity funds (large-, mid-, and small-cap, and A-REIT), 280 international equity funds, and 70 Australian bond funds
Biased Shorts: Short sellers’ Disposition Effect and Limits to ArbitrageTrading Game Pty Ltd
Abstract: We investigate whether short sellers are subject to the disposition effect using a novel dataset that allows to identify the closing of short positions. Consistent with the disposition effect, short sellers are more likely to close a position the higher their capital gains.
Furthermore, stocks with high short sale capital gains experience negative returns, suggesting that their disposition effect has an effect on stock prices. A trading strategy based on this finding achieves significant three-factor alphas. Overall, short sellers’ behavioral biases limit their ability to arbitrage away the mispricing caused by the disposition effect of other market participants.
Behavioral economics emerged in the 1980s, above all because of the creative work of Richard Thaler, exploring the relevance of the endowment effect, mental accounting, concern for fairness, and other “anomalies” from the standpoint of standard economic theory. His engaging book, Misbehaving, offers a narrative account of how these ideas came about, and also explores some of their implications for the future. Continuing challenges include making predictions when behavioral findings cut in different directions (as, for example, where optimistic bias conflicts with availability bias); understanding the line between nudging and manipulation; and applying behavioral findings to pressing public policy challenges, such as poverty, education, terrorism, and climate change.
VAT Registration Outlined In UAE: Benefits and Requirementsuae taxgpt
Vat Registration is a legal obligation for businesses meeting the threshold requirement, helping companies avoid fines and ramifications. Contact now!
https://viralsocialtrends.com/vat-registration-outlined-in-uae/
What are the main advantages of using HR recruiter services.pdfHumanResourceDimensi1
HR recruiter services offer top talents to companies according to their specific needs. They handle all recruitment tasks from job posting to onboarding and help companies concentrate on their business growth. With their expertise and years of experience, they streamline the hiring process and save time and resources for the company.
[Note: This is a partial preview. To download this presentation, visit:
https://www.oeconsulting.com.sg/training-presentations]
Sustainability has become an increasingly critical topic as the world recognizes the need to protect our planet and its resources for future generations. Sustainability means meeting our current needs without compromising the ability of future generations to meet theirs. It involves long-term planning and consideration of the consequences of our actions. The goal is to create strategies that ensure the long-term viability of People, Planet, and Profit.
Leading companies such as Nike, Toyota, and Siemens are prioritizing sustainable innovation in their business models, setting an example for others to follow. In this Sustainability training presentation, you will learn key concepts, principles, and practices of sustainability applicable across industries. This training aims to create awareness and educate employees, senior executives, consultants, and other key stakeholders, including investors, policymakers, and supply chain partners, on the importance and implementation of sustainability.
LEARNING OBJECTIVES
1. Develop a comprehensive understanding of the fundamental principles and concepts that form the foundation of sustainability within corporate environments.
2. Explore the sustainability implementation model, focusing on effective measures and reporting strategies to track and communicate sustainability efforts.
3. Identify and define best practices and critical success factors essential for achieving sustainability goals within organizations.
CONTENTS
1. Introduction and Key Concepts of Sustainability
2. Principles and Practices of Sustainability
3. Measures and Reporting in Sustainability
4. Sustainability Implementation & Best Practices
To download the complete presentation, visit: https://www.oeconsulting.com.sg/training-presentations
The world of search engine optimization (SEO) is buzzing with discussions after Google confirmed that around 2,500 leaked internal documents related to its Search feature are indeed authentic. The revelation has sparked significant concerns within the SEO community. The leaked documents were initially reported by SEO experts Rand Fishkin and Mike King, igniting widespread analysis and discourse. For More Info:- https://news.arihantwebtech.com/search-disrupted-googles-leaked-documents-rock-the-seo-world/
Putting the SPARK into Virtual Training.pptxCynthia Clay
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Analyzing the Bitcoin Ponzi Scheme Ecosystem
1. Analyzing the Bitcoin Ponzi Scheme Ecosystem
Marie Vasek and Tyler Moore
1
Computer Science, University of New Mexico, lastname@cs.unm.edu
2
Tandy School of Computer Science, The University of Tulsa,
firstname-lastname@utulsa.edu
Abstract. This paper analyzes the supply and demand for Bitcoin-
based Ponzi schemes. There are a variety of these types of scams: from
long cons such as Bitcoin Savings & Trust to overnight doubling schemes
that do not take off. We investigate what makes some Ponzi schemes suc-
cessful and others less so. By scouring 11 424 threads on bitcointalk.
org, we identify 1 780 distinct scams. Of these, half lasted a week or less.
Using survival analysis, we identify factors that affect scam persistence.
One approach that appears to elongate the life of the scam is when the
scammer interacts a lot with their victims, such as by posting more than
a quarter of the comments in the related thread. By contrast, we also
find that scams are shorter-lived when the scammers register their ac-
count on the same day that they post about their scam. Surprisingly,
more daily posts by victims is associated with the scam ending sooner.
Keywords: Bitcoin, cybercrime measurement
1 Introduction
Bitcoin draws out risk-seeking individuals. The exchange rate is volatile; many
businesses built on top of it are speculative in nature; the currency is pseu-
doanonymous and distributed. Consequently, it is perhaps unsurprising that
many Bitcoin users have taken to Ponzi schemes (and Ponzi scheme runners
to Bitcoin).
In this paper, we look at the ecosystem around Ponzi schemes advertised to
Bitcoin users. Others have established a lower bound for the amount of money
earned by criminals through Bitcoin scams. Here we more comprehensively study
the scams by gathering data where they are promoted. As well as shedding light
on the “supply” side of Ponzi schemes, we also look at the “demand” side by
gathering data on victim interactions with the scams. People keep falling for
Bitcoin scams, but why? Bitcoin users like to purport themselves as particu-
larly technologically savvy, but does that help or hinder their susceptibility to
scams? How do the steps taken by scammers, such as engaging shills to promote
their products, affect their success? Ultimately, our goal is to shed light on why
criminals are able to prosper in this ecosystem.
Even with the improved coverage relative to previous work, our results are
necessarily incomplete. There are inevitably scams which use Bitcoin and we
2. do not measure. There are also scammers which create multiple accounts to
talk about their scam and we only are able to extricate the obvious cases of
this behavior. Despite these limitations, we provide a large-scale analysis of this
online Ponzi scheme ecosystem.
The research contributions for this paper are both in the data collection
methodology and in the analysis of the gathered data.
– Section 2 outlines our data collection contributions: gathering candidate
scam data directly from scammer advertising venues, automatically con-
firming scams by inspecting payout mechanisms, and, for confirmed scams,
collecting usage, performance and demographic indicators from forum posts.
This yields a richer dataset on Ponzi schemes than has been collected before
in prior work.
– Our data analysis contributions (found in Section 3) leverage this novel
dataset to describe supply-side characteristics of scams and scammers as
well as describe demand-side characteristics of victims.
2 Methodology
We aim to measure scams by collecting data from the places they are advertised.
This helps us generate a comprehensive list of advertised scams. For the purposes
of this study, we elect to focus on Ponzi schemes exclusively. Of course, there
are many different types of scams affecting Bitcoin, as shown by Vasek and
Moore [12]. We focus on Ponzi schemes due to their reliance on public advertising
and the consistency of locations for such advertising. Since Ponzi schemes must
advertise to stay in business, we are relatively confident in the comprehensiveness
of our approach.
We collect our data from the forum bitcointalk.org. This forum was cre-
ated in the same year as Bitcoin and by the same pseudonymous entity3
. This
forum is the top place where Bitcoin community members go to discuss Bitcoin
and is currently one of the 1 000 most popular websites in the world, according
to Alexa. We chose this as our sole source for this work based both on its popu-
larity in the Bitcoin ecosystem and its popularity within the subsection of Ponzi
scheme investors within the Bitcoin ecosystem, as we found in our previous work
in this space [12].
In order to collect information about the scams, we crawl the entire history
of three subforums of bitcointalk.org: Scam accusations, Gambling: Games
and Rounds, and Gambling: Investment Games. Investment games is a subfo-
rum where users submit Ponzi schemes or moderators move threads on Ponzi
schemes. We can find a number of Ponzi schemes advertised in other subforums
of bitcointalk. However, we choose the two most popular subforums for Ponzi
schemes that had the highest signal to noise ratio: scam accusations and games
and rounds. In total, we crawl 11 424 threads on these three subforums from
June 2011 through November 2016. We consider all the subforums of bitcointalk
3
https://bitcointalk.org/index.php?topic=5
3. where we found any posts advertising a Ponzi scheme. We then look at the
forums, particularly for Ponzi schemes. We omit subforums like the gambling
subforum which predominantly contained posts about online card games and
other non-Ponzi scheme activity.
Fig. 1: Screenshots of the initial posting for the Ponzi scheme and an example
victim response.
Since threads on these forums cover other topics than just promoting Ponzi
schemes, we refine this further to threads that referenced “ponzi” or “hyip” in
the first 10 comments. We then process these further to only consider threads
which contained a URL or bitcoin address for the scam. This left us with 1 810
scams advertised through 1 804 Ponzi-registered domains, as well as 1 448 Bitcoin
addresses collated from 2 617 threads. We merge threads containing the same
domain or Bitcoin address, since many scams were advertised multiple times
or in different places. Note that we throw out threads containing a whitelist
of legitimate gambling domains4
. We also do not consider popular domains,
removing from consideration any URLs in the Alexa top 10 000 domains such as
google.com and wikipedia.org.
Our objective is to extract as much information about reflecting supply and
demand for scams by examining threads discussing the schemes. In particular, we
are interested in measuring the lifetime of the scam, the profiles of the scammers
and their victims, and how interactive the threads on scams are. We considered
the opening time a scheme was operational to be the first time it was advertised
on bitcointalk and the closing time to be the last comment time on threads
relating to the scheme. The difference between these times is the lifetime of the
scam. We closely analyzed 10 different scams for which we had ground truth on
4
This list was curated by bitcointalk user mem here: https://bitcointalk.org/
index.php?topic=75883.0.
4. the lifetime of the scam, and found that this method was reasonably accurate
within a couple days of the length of the scam.
We identify three distinct categories of posters: scammers, victims, and shills.
We consider the scammer to be the original poster about the scheme and the
victims to be the commenters who were not the scammer or a shill. For each
scammer and victim, we analyze their most recent posting history (maximum 20
posts). We parse out the other subforums they posted in as well as the number of
times they posted on any given Ponzi-related thread. For scammers, we identify
their public interaction with victims; similarly, for victims, we identify their
public interactions with scammers. We also find evidence of every user’s public
history on the forums.
We classify shills as victims who post only about a single scam and nowhere
else on the forum. We devise this rule upon looking through scam threads and
finding users who were extremely positive. Some of these users posted about
multiple threads, seemingly different content, and largely had corroborating ev-
idence, such as transaction information. Others only posted about one or a few
scams with similar content. We attempt to identify these posters automatically,
and the most straightforward way is by number of threads posted on. While not
all shills only post about one particular scam and not all posters with history on
only one scammer thread are shills, we have concluded from manual inspection
that this simple approach provides an effective approach to identify many shills
without miscategorizing legitimate users.
Finally, we sought a way to measure the effort the scammer made to imbue
trust in his scheme from the Bitcoin forum. The markers of trust and reputation
that we use include the time between registration and posting about a scam
(with shorter gaps seemingly less trustworthy) and the overall posting history of
the scammer including frequency and topics.
3 Results
We find 1 780 scams from 1 956 scammers on 2 625 forum posts. Scams with mul-
tiple scammers have multiple threads about the scam originating from different
usernames. By randomly inspecting 20 such instances of this, we find that in
most cases, both usernames appear to be the same scammer or at least oper-
ating the same scam. We identify 11 990 users who posted in response to these
posts.
Figure 2 shows the lifetimes of the scams, where lifetime is measured as the
length of time between the first post about a given scam and the last. About a
quarter of the attempted scams did not last a day and half only lasted a week.
However, some scams lasted a long time, with the longest lasting scam lasting
over three years. From manual inspection, many of the scams lasting a day were
shut down by the moderators or other entities. The rest of this section will
break down this vast difference in lifetimes between these scams and quantify
the differences both in attacker strategies and in victimology.
5. 1 5 10 50 100 500 1000
0.00.20.40.60.81.0
Lifetime of Scams
Days on Forum
SurvivalProbability
Fig. 2: Survival analysis of the lifetime of scams.
3.1 Scammer Interaction and Scam Lifetime
Figure 3 shows the difference in lifetime based on the amount of scammer inter-
action. Out of the 344 threads that only had one post by the scammer on them,
less than 50% lasted longer than a day – 19 of them only consisted of one post
total. We find that more scammer posting helped enliven the scam – whereas an
average scam lasted about a week, the average scam where the scammer posted
at least half of the posts lasted about three weeks. Scammers interacting with
their victims seem to prop up their scam, at least in the short term. The differ-
ence in these curves, measured by running the survival curve difference test, is
statistically significant at the p=0.01 level.
We can see if we can see the same effect for shills as well as scammers, since
most of the postings by scammers seems rather overt. Figure 4 shows the average
lifetime of a scam based on the percentage of posts by shills. Scams where more
than 10% of the posts are from shills last longer than those where more than
10% of the posts are from scammers. Furthermore, more shill posts seems to be
more effective than the combined strategy, considering both shill posts and scam
posts to contribute to the lifetime. Running a survival curve differences test, the
effect of the differing shill interaction percentages on the lifetime of a scam are
statistically significantly different at the p=0.1 level.
We indirectly measure scammer reputation in two ways: by examining where
scammers post and by measuring the time between registration and scam post-
ing. Figure 5 shows the breakdown in the efficacy of the scam by the reputation of
the scammer. On the left we look at the other posts/comments made by the user
who first posted the scam. We distinguish between only posting on one scam,
only posting on (multiple) scam posts, and those scammers who post in other
parts of bitcointalk. We notice that scammers that only post on one scam have
a lower lifetime compared to scammers that post outside of just one scam. The
6. 1 2 5 10 20 50 100 200 500
0.00.20.40.60.81.0
Lifetime of Scams
Days on Forum
SurvivalProbability
Only initial posting
>0.25 of the comments
>0.5 of the comments
Fig. 3: Lifetime of the scam based on the fraction of the comments about the
scam from the scammer.
difference in these survival lifetimes are significant at the p=0.01 level. Figure 5b
shows the lifetime based on if the scammer account was created on the same day
as the scam or not. 39% of scammer accounts were created within a day as the
corresponding bitcointalk post. We discover that scams advertised by scammer
with newly created accounts die quicker than those with older accounts. Half of
scams that have been created at least a day prior to posting end within 26 days
compared to only 4 days for those created the same day. The difference in these
survival plots is statistically significant at the p=0.01 level.
3.2 Victim Behavior
We measure the responses from 11 902 victims from 89 439 comments on 2 629
threads on 1 779 scams. In this section, we examine characteristics of the user
accounts that post in threads about Ponzi schemes.
In Figure 4 we separate out shills from the victims and the scammers. We can
see that shill and scammer activity are associated with longer lifetimes. Active
shills do appear to survive slightly longer than active scammers for the first
couple of months, but the overall effect is indistinguishable between shills and
scammers.
Table 1 shows how Ponzi scheme victims’ post history compares to that of
other users active on bitcointalk. For this, we scrape bitcointalk’s aggregated
posts statistics for ground truth and categorize each post using bitcointalk’s
categories. The Ponzi victims’ post history is statistically significantly different
(at the p=0.01 level) than the general post history, both aggregating by thread
and by overall topic. Ponzi victims are overrepresented in the “economy” section,
which is unsurprising since this is the section where Ponzi scheme advertisements
7. 1 2 5 10 20 50 100 200 500
0.00.20.40.60.81.0
Lifetime of Scams
Days on Forum
SurvivalProbability
Only initial posting
shill >0.1 of the comments
scammer >0.10 of the comments
scam or shill >0.25 of the comments
Fig. 4: Lifetime of the scam by interaction by “shill” commenters.
are located. Ponzi victims are also overrepresented in the “other” section. When
we look further into this forum category, we find that Ponzi victims are overrepre-
sented in the “Off Topic” and “meta” board commenters and under represented
in “Politics & Society” and “Beginners”. We also see Ponzi victims underrep-
resented in many technical boards, like “Development & Technical Discussion”
and “Mining” but are overrepresented in “Mining Speculation”.
We can also observe what time these victims posted on threads about the
scheme. The median time for victims to comment on a thread is about 5 days
after the initial post. Figure 6 analyzes this effect further. While most victims
post within a week, there is quite a long tail of victim posts. We discover new
victims posting over half a year after the start of the initial scam posting.
3.3 Proportional Hazards Model
To distill the varying effects on the lifetime of a Ponzi scheme, we run a Cox
proportional hazards model. Our dependent variable is the lifetime of the scam,
measured in days. For independent variables, we use the following:
daily # victim comments This measures the number of victim comments
over the lifetime of the scam. We use a daily count, since the overall count
is, unsurprisingly, highly correlated with the lifetime of the scam.
daily # scammer comments This measures the number of scammer com-
ments over the lifetime of the scam. Again, we use a daily count to control
for the correlation between this variable and the lifetime of the scam.
shill has posted? This is true if a “shill” (described more thoroughly in
Section 3.1) has posted anywhere in the thread. This accounts for their
presence, since the number of comments by these users is so low.
8. 1 5 10 50 100 500 1000
0.00.20.40.60.81.0
Lifetime of Scams
Days on Forum
SurvivalProbability Only One Scam
Only on Scam Posts
General Posting
(a) Lifetime of scams, distinguishing be-
tween post history.
1 5 10 50 100 500 1000
0.00.20.40.60.81.0
Lifetime of Scams
Days on Forum
SurvivalProbability
Old account
Same day account
(b) Lifetime of scams, distinguishing be-
tween newly created accounts and older
accounts.
Fig. 5: Measuring lifetimes of scams based on attacker accounts.
Within a day 1 day 2−7 days 8−14 days 15−21 days 22−28 days 29−56 days 57−112 days >113 days
050001500025000
Fig. 6: Number of victim posts after a thread starts.
same day account This is true if the scammers’ bitcointalk account was
registered the same day as the original post for the scam.
Table 2 shows the results of running this regression. We note that all the
variables are statistically significant to at least the p = 0.05 level, with three of
the variables highly significant. The best way to interpret the table is to focus
on the exp(coef) column. Values greater than one correspond to an increase in
the hazard rate, while those less than one correspond to a decrease. The hazard
rate captures the instantaneous probability that a scam will shut down, so an
increased hazard rate means a greater risk of shutdown.
Each additional daily comment by a victim correlates to a 2.9% increase in the
hazard rate. The effect is similar, though slightly weaker, for additional posts by
the scammer. The result is somewhat counterintuitive; one might have expected
9. Category # Victim Posts # Other Posts
Altcoins (all) 32 536 5 429 022 (–)
Alternative Clients 106 54 159 (–)
Bitcoin Discussion 8 872 998 246 (+)
Development & Technical Discussion 683 162 405 (–)
Group Buys 498 84 734
Hardware 2 730 518 728 (–)
Mining 427 1 044 148 (–)
Mining software (miners) 274 67 561 (–)
Mining speculation 616 63 071 (+)
Pools 885 177 985 (–)
Press 696 74 437 (+)
Project Development 1 526 137 245 (+)
Technical Support 586 58 952 (+)
Auctions 1 865 108 048 (+)
Collectibles 1 063 60 745 (+)
Computer hardware 1 462 118 584 (+)
Currency exchange 3 124 138 264 (+)
Digital goods 7 303 277 903 (+)
Economics 3 692 1 204 450 (–)
Gambling 12 070 1 297 038 (+)
Gambling discussion 5 677 340 593 (+)
Games and rounds 23 331 388 689 (+)
Goods 1 251 587 681 (–)
Investor-based games 15 402 115 454 (+)
Lending 3 230 138 108 (+)
Marketplace 517 5 372 844 (–)
Micro Earnings 3 694 144 797 (+)
Scam Accusations 4 643 116 151 (+)
Securities 1 338 202 813
Service Announcements 2 338 288 993 (+)
Service Discussion 3 692 330 535 (+)
Services 8 528 407 342 (+)
Speculation 5 058 883 584 (–)
Trading Discussion 1 678 257 930
Local (all) 14 932 4 454 405 (–)
Archival 1 026 147 836
Beginners & Help 3 923 564 720
Meta 1 960 134 319 (+)
Off-topic 8 309 563 710 (+)
Politics & Society 2 181 290 782
Table 1: Bitcointalk forum categories and where scam victims post. Categories
are marked as under or overrepresented according to a chi-squared test with
97.5% confidence. Categories with at least 50 000 posts are included.
10. coef exp(coef) 95% CI p value
Daily # victim comments 0.028 1.029 (1.022 , 1.036) 0.0001
Daily # scammer comments 0.022 1.022 (1.002 , 1.043) 0.034
Shill has posted? -0.846 0.429 (0.385 , 0.479) 0.0001
Same day account 0.374 1.453 (1.320 , 1.599) 0.0001
Log-rank test: Q = 489.2, p 0.0001, R2
= 0.218.
Table 2: Cox proportional hazards model: measuring scammer and victim effects
on the lifetime of the scam.
scams with more active participation to be longer-lived, yet the opposite is true.
One possible explanation is that victims are more likely to post when there are
problems, and so are scammers.
By contrast, a shill posting on a thread is correlated with a massive 57%
decrease in the hazard rate. This indicates that shills may play a significant role
in prolonging the lives of scams, helping to draw in more victims and settle the
nerves of existing investors.
Unsurprisingly, a scammer creating an account on the same day as the initial
post correlates with a shorter scam lifetime. This confirms the intuition from
Figure 5, which suggests that no post history shortens the lifetime of the scam.
The Cox model shows that scams created by newly registered posters face a 45%
increase in the hazard rate.
Reflecting on the overall model, we conclude that posts by shills may prolong
a scam’s lifetime dramatically, whereas posts made by victims and scammers
have the opposite effect. Finally, the reputation of posters as indicated by posting
history also appears to significantly affect the scam’s expected lifetime.
4 Related Work
This paper fits into the greater literature of reputation mechanisms. Resnick
et al. provide a general overview for reputation systems as well as drawbacks
in them [9]. Shen et al. provide analysis of reviewers posting about products
on online retailers [10]. They found that popular reviewers post about popular
products that have few reviews and also tend to provide similar reviews to the
existing ones about the product.
This paper also fits into greater literature about Bitcoin. Bitcoin has a small
community of actors [2]. Maurer et al. associated the distributed network of
Bitcoin nodes with the distributed network of conversations, like those found
on the Bitcoin forums [6]. We agree that the sociality of trust that Bitcoin
offers seems to be both ingrained in the code and the community. We use this
small network of trust ingrained in code and in people to more easily measure
communications.
11. To this end, other researchers have mined Bitcoin forum posts to infer activ-
ity in the Bitcoin ecosystem. Vasek et al. searched for reports of DDoS attacks
to infer after the fact when they occurred [13]. Fleder et al. searched for Bitcoin
addresses to categorize them [4]. Using this information, they were able to tie
bitcointalk users to Silk Road transactions. Similarly, Vasek and Moore use bit-
cointalk to identify addresses for potential Bitcoin scams [12] and Liao et al. use
the Bitcoin subreddit to seed their ransomware address finder [5]. Most similarly
to this paper’s methodology, Xie et al. analyze how, among other things, the
social network in the Bitcoin forums leads to price swings in Bitcoin [14]. They
found that bitcointalk users that invite long discussions are more likely to share
relevant information. When looking at the connectedness of bitcointalk users,
they found that the more connected the users are at a given time, the more
intense the trading frequency is.
Our work also falls in the literature on online Ponzi schemes, also known as
high yield investment programs (HYIPs). Moore et al. overviewed the ecosystem
using HYIP aggregator websites [7]. They found that the lifetime of any given
HYIP could be predicted by interest payments and the mandatory investment
term. Neisius and Clayton followed up on this work, concentrating on the in-
centives promoting this criminal behaviors [8]. They found that HYIP operators
paid to be listed on aggregator websites and also received a referral bonus for
users directed to HYIPs. They also crawled the criminal forums behind people
that run HYIPs and HYIP aggregator websites, and found that the majority of
these criminals are based in the US. Drew and Moore found clusters of replicated
HYIP websites, pointing to the high use of HYIP kits in creating Ponzi scheme
websites [3]. Vasek and Moore carried out the first analysis of Bitcoin-based
Ponzi schemes [12]. They directly measured the profits of 32 Ponzi schemes and
found that these scammers were bringing in over $7 million. Bartoletti et al.
analyzed Ponzi schemes using the cryptocurrency Ethereum and found similar
results as Vasek and Moore found with Bitcoin-based Ponzi scams [1][12]. Soska
and Christin looked at online black marketplaces and found that some would
“exit scam” or run the marketplace legitimately for a time and then take all
the money deposited in it and leave [11]. They found that this behavior lowered
users’ confidences in these marketplaces for a couple months, but long term, the
online drug market was resilient to these scams.
5 Conclusion
Bitcoin Ponzi schemes are alluring. The victims of these scams enjoy the thrill
of the risk and the opportunity to earn a windfall. The scammers are seduced
by the opportunity to earn hard-to-trace money with seemingly little effort.
To measure this, we crawl 11 424 threads on three subforums of the Bitcoin
forums from June 2011 through November 2016 to find 1 780 scams from 1 956
scammers on 2 625 forum posts targeting 11 990 users. We find that more daily
scammer and victim interaction shortens the life of the scam. Furthermore, we
analyze that shill interaction, or users that only post in one thread, and discover
12. that it lengthens the life of the scam. We demonstrate that having a reputation
on the Bitcoin forum matters: posting a scam the same day as an account was
created is associated with a quicker demise.
In addition to investigating perpetrators of these frauds, we also analyze the
users who fall victim to them. We compare the post history of scam victims to
overall Bitcoin forum statistics and find that scam victims disproportionately
post in other forums like “Off-Topic” and “Mining Speculation”. We find that
most victims post within the first five days of a scam post, with a long tail that
post even over a year after the initial posting.
References
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ponzi schemes on Ethereum: identification, analysis, and impact. arXiv preprint
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4. Michael Fleder, Michael S Kester, and Sudeep Pillai. Bitcoin transaction graph
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