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Open Source Finance: QuantLib, OpenGamma, Bitcoin

Ferdinando M. Ametrano
December 04, 2014
5.2k

Open Source Finance: QuantLib, OpenGamma, Bitcoin

Keynote speech at the 2014 QuantLib User Meeting in Düsseldorf

A comparison between the most relevant Open Source Finance projects, with an introduction to the most relevant one: Bitcoin.

Ferdinando M. Ametrano

December 04, 2014
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Transcript

  1. Open Source Finance:
    QuantLib, OpenGamma, and Bitcoin
    Ferdinando M. Ametrano
    [email protected]
    Banca IMI IntesaSanpaolo
    Milano-Bicocca University
    QuantLib
    Hayek Money
    Düsseldorf , 4th of December 2014, QuantLib User Meeting
    https://speakerdeck.com/nando1970/open-source-finance-quantlib-opengamma-bitcoin

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  2. Open Source Software
    software that can be freely
    • used,
    • changed,
    • and shared (in modified or unmodified form)
    • by anyone
    http://opensource.org/
    2/83

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  3. Free Software
    A software is free if its users have four essential
    freedoms:
    1. The freedom to run the program as you wish, for
    any purpose
    2. The freedom to study how the program works,
    and change it so it does your computing as you
    wish.
    3. The freedom to redistribute copies.
    4. The freedom to distribute copies of your
    modified versions to others.
    3/83

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  4. Open Source / Free Finance
    • QuantLib
    • OpenGamma
    • Bitcoin
    4/83

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  5. QuantLib
    • The announcement:
    5/83

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  6. QuantLib
    • SourceForge project registered on 2000-10-11
    • First release 2000-12-05
    • http://quantlib.org
    6/83

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  7. QuantLib (2)
    https://github.com/lballabio/quantlib
    • Commits: 17,078
    • Contributors: 25
    • Watch: 103
    • Stars: 247
    • Forks: 293
    • Pull Requests: 173 since June 2013
    7/83

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  8. QuantLib (3)
    8/83

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  9. 9/83

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  10. OpenGamma
    www.opengamma.com
    • Founded in 2009
    • Raised a total of $23.35 million from Accel
    Partners, Firstmark Capital, ICAP and Euclid
    Opportunities
    • Headquartered in London with an office in
    New York City
    • 70% of employees in R&D
    10/83

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  11. OpenGamma (2)
    • Open architecture platform for real-time
    market risk management
    • Strong Java analytics library (adjoint greeks)
    11/83

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  12. OpenGamma (3)
    https://github.com/OpenGamma
    • Commits: 26,700
    • Contributors: 33
    • Watch: 32
    • Stars: 184
    • Forks: 123
    • Pull Requests: 294 since November 2012
    12/83

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  13. OpenGamma (4)
    13/83

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  14. Bitcoin: The Announcement
    From: Satoshi Nakamoto vistomail.com>
    Subject: Bitcoin P2P e-cash paper
    Newsgroups: gmane.comp.encryption.general
    Date: 2008-10-31 18:10:00 GMT
    I've been working on a new electronic cash system that's fully
    peer-to-peer, with no trusted third party.
    The paper is available at:
    http://www.bitcoin.org/bitcoin.pdf
    The main properties:
    Double-spending is prevented with a peer-to-peer network.
    No mint or other trusted parties.
    Participants can be anonymous.
    New coins are made from Hashcash style proof-of-work.
    The proof-of-work for new coin generation also powers the
    network to prevent double-spending.
    Bitcoin: A Peer-to-Peer Electronic Cash System
    Abstract. A purely peer-to-peer version of electronic cash […]
    Satoshi Nakamoto
    ---------------------------------------
    The Cryptography Mailing List
    14/83

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  15. Satoshi Nakamoto
    • Unknown identity: pseudonymous person or group?
    • Worked on Bitcoin since 2007, published the paper in 2008
    • Released as open source free software in January 2009
    • His involvement stops mid-2010
    • Entrusted the Bitcoin SourceForge project and a copy of the
    alert key to Gavin Andresen, effectively his successor
    • Must own about 1M bitcoins, never spent
    Bitcoin: A peer-to-peer electronic cash system
    http://www.bitcoin.org/bitcoin.pdf
    http://mag.newsweek.com/2014/03/14/bitcoin-satoshi-nakamoto.html
    15/83

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  16. Bitcoin
    • SourceForge project registered on 2008-11-09
    • First release 2009-01
    • https://bitcoin.org
    16/83

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  17. Bitcoin (2)
    https://github.com/bitcoin/bitcoin
    • Commits: 7,481
    • Contributors: 262
    • Watch: 798
    • Stars: 6125
    • Forks: 4452
    • Pull Requests: 3500+ since December 2010
    17/83

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  18. Bitcoin (3)
    18/83

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  19. Open Source Finance
    • Finance is usually closed source
    • Academia has not adopted QuantLib and
    OpenGamma very much
    • Bitcoin is the most relevant open source
    finance project
    • Why so much relevant?
    19/83

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  20. Favorable Opinions
    • Ben Bernanke: [the virtual currency] may hold
    long-term promise, particularly if the
    innovations promote a faster, more secure and
    more efficient payment system.
    • Jared Cohen: I think it’s very obvious to all of
    us that crypto-currencies are inevitable
    • Marc Andreessen: Bitcoin today is like
    Internet in 1994, weird and scary
    20/83

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  21. Bitcoin Investments to Surpass Early
    Stage Internet Investments
    • f
    21/83

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  22. Unfavorable Opinions
    • Nouriel Roubini: Bitcoin is not a currency as it is
    not a unit of account or a means of payments or
    store of value. It is a Ponzi game and a conduit for
    criminal/illegal activities
    • Alan Greenspan: It’s a bubble. It has to have
    intrinsic value: you have to really stretch your
    imagination to infer what the intrinsic value of
    Bitcoin is. I haven’t been able to do it. Maybe
    somebody else can. I do not understand where
    the backing of Bitcoin is coming from
    22/83

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  23. What are bitcoins?
    https://bitcoin.org/en/
    • decentralized digital currency
    • not backed by any government or organization
    • instantaneous peer-to-peer transactions
    • no need for trusted third party
    • cryptographic security
    • low-cost banking for everybody everywhere
    https://bitcoin.org/en/faq
    http://www.coindesk.com/information/
    23/83

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  24. Bitcoin Economy
    • Total number of BTC is about 13M
    • Market Cap: $7B BTC vs $1,200B USD
    24/83

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  25. December 2013: China crackdown
    • People’s Bank of China crackdown:
    – prohibits financial institutions from trading,
    underwriting, or offering insurance in bitcoins or any
    other digital currency
    – Bitcoin is not to be considered a currency
    – owning bitcoins is not outlawed or prohibited
    • As of December 2013 BTC China was world's
    largest Bitcoin exchange by volume
    • Alibaba, China's top Internet retailer, stopped
    using bitcoins as of January 19 2014.
    25/83

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  26. February 2014: Mt Gox bankruptcy
    • As of January 2014 Mt Gox was world's largest
    Bitcoin exchange by volume
    • In February 2014 it filed for bankruptcy
    protection from creditors
    • It announced that around 850,000 bitcoins
    belonging to customers and the company
    were missing and likely stolen, an amount
    valued at more than $450 million at the time
    • Fraud or theft?
    26/83

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  27. Silk Road
    • online market, operated as a Tor hidden service
    • online users were able to buy illicit goodies using
    bitcoins, while browsing it anonymously and
    securely without potential traffic monitoring
    • launched in February 2011, shut down in October
    2013
    • Ross William Ulbricht, alleged to be the owner of
    Silk Road arrested in San Francisco
    • Many other black markets have filled in as
    successors
    27/83

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  28. Bitcoin resilience
    Is there anything else in financial world:
    • Just 5 years old
    • Without government or corporation backing
    • That can lost its main (China) market and its main
    exchanges in 3 months
    • Subjected to fraud or theft perpetrated at its
    main reference exchange
    • With such a bad reputation
    That could be still alive and kicking?
    28/83

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  29. Hard to regulate
    • Janet Yellen (November 2013 US Senate):
    – Bitcoin is a payment innovation that's taking place
    outside the banking industry
    – It's not so easy to regulate Bitcoin because there's no
    central issuer or network operator. This is a
    decentralized, global [entity]
    • ECB (October 2012 report):
    – governments and central banks would face serious
    difficulties if they tried to control or ban any virtual
    currency scheme
    – there is no server that could be shut down if the
    authorities deemed it necessary
    29/83

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  30. Disruptive?
    • PayPal or Western Union did not received the
    attention of virtually every central bank
    • For a first evidence of bitcoin relevance look at
    the on-going debate about it
    30/83

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  31. Bitcoin Price Growth & Adoption
    Coindesk, State of Bitcoin Q2 2014
    http://www.coindesk.com/state-of-bitcoin-q2-2014-report-expanding-bitcoin-economy/
    31/83

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  32. Merchants & Payment Processors
    • PayPal accept bitcoin as of September 2014
    • Sridhar Ramaswamy, head of Google Wallet
    We are working in the payments team to figure out
    how to incorporate bitcoin into our plans
    • Amazon: granted patent for the use of digital
    currencies as payment on cloud platforms
    (Amazon Web Services)
    32/83

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  33. Where can you buy bitcoins?
    What can you buy with bitcoins?
    • Buy bitcoins using USD or EUR at one of many
    exchanges, e.g. Bitstamp, The Rock Trading, etc.
    • Use bitcoins to buy:
    – web services
    – software
    – hardware
    – gambling services
    – Narcotics, guns, credit card numbers, etc.
    – Topping the list, in terms of the number of
    transactions, is tipping and donations
    33/83

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  34. Bitcoin: a currency and a protocol
    • Bitcoin: protocol, software, and community
    • bitcoins: units of the currency.
    bitcoins are sent using Bitcoin
    34/83

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  35. Bitcoin the protocol
    Distributed public ledger of transactions:
    • allows to transfer a unique digital token
    • the token can be exchanged, but not duplicated
    • keeps records of each and every transaction
    forever
    • shared with peer-to-peer technology
    • everyone knows the transaction happened,
    nobody can challenge its legitimacy
    • the protocol is Bitcoin extra-legal tight regulation
    35/83

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  36. bitcoin the currency
    • bitcoins are a digital property
    • created inside the Bitcoin protocol
    • the first powerful protocol application
    • authorities replaced:
    – central banks
    – financial intermediaries
    36/83

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  37. bitcoins
    • Not to be found anywhere, they only exist as
    block chain documented transactions
    • A bitcoin wallet is a public address
    1FEz167JCVgBvhJBahpzmrsTNewhiwgWVG
    • the public ledger certifies for everybody how
    many bitcoins are associated to the wallet
    http://blockexplorer.com/address/1FEz167JCVgBvhJBahpzmrsTNewhiwgWVG
    It is mine; you
    are REALLY
    encouraged to
    tip
    37/83

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  38. Pseudonymity, Anonymity
    Bitcoin is really pseudonymous, not anonymous:
    • The public key does not provide direct
    information about the private key owner
    • All transactions are transparent to everybody’s
    inspection.
    • Perfect persistent public account history: the
    public ledger is forever
    • Tool little privacy for honest people, too much for
    criminals
    https://blockchain.info/
    http://blockexplorer.com/
    38/83

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  39. Asymmetric Cryptography:
    Public/Private Key Pair
    mathematically linked, perform opposite functions:
    • private (secret) key produce a digital signature
    • public key used by anyone to verify the signature
    • The bitcoin wallet address is the public key
    • The private key allows spending from the wallet
    39/83

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  40. Asymmetric Cryptography:
    Public/Private Key Pair
    Keys are not granted by the network:
    • No need to register the keys anywhere in
    advance
    • Only used when required for a transaction
    40/83

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  41. A bitcoin transaction:
    from public key to public key
    • The sender’s private key signs the transaction:
    – transacted amount
    – receiver’s public key
    • Sender’s public key verifies that the transaction:
    – originated from sender’s private key
    – has not been modified
    – the amount is at sender’s public key disposal
    • The transaction is published to the public ledger
    • Everybody knows that the receiver’s public key
    has received the transacted amount
    41/83

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  42. Bitcoin wallet security
    • bitcoins are effectively owned by whoever
    can spend them
    • Securing a wallet: private key safe storage
    • PC client: Bitcoin Core, Armory, Electrum
    • Web client: blockchain.info, greenaddress.it
    • Cold storage: never exposed to Internet,
    stored away
    42/83

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  43. Bitcoin’s public ledger: the block chain
    • Transactions are bundled in blocks, sequentially
    chained, about one block every 10 minutes
    • The block chain is a history of transactions
    resilient to network attackers
    • The cryptographic link between blocks requires
    large amount of computing power, so the block
    chain cannot be altered without huge resources
    • Computing power is measured in hash/s, hash
    being the basic operation needed for validation
    43/83

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  44. Network hash rate
    • More powerful than the combined top 500
    supercomputers (but less flexibility…)
    • charts
    44/83

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  45. Mining
    • Miners are the nodes of the network
    • They provide the computing power for:
    – processing and validating transactions (avoiding
    double spending)
    – securing the network
    – synchronizing the nodes
    45/83

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  46. Mining (2)
    • Miners compete to process a new block of
    transactions.
    • The winner provides a proof-of-work and is
    rewarded with the issue of new bitcoins.
    • Seigniorage revenues subsidize the network,
    making transaction almost free
    46/83

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  47. Bitcoin Monetary Rule
    • 2009: 50BTC every 10 minutes
    – halving every 4Y
    • This is the only way new bitcoins are released
    • It is called mining because of its similarity with
    the progressive scarcity of gold extraction
    • digital cash supply free of discretionary
    intervention
    47/83

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  48. Inelastic Money Supply
    Decreasing rate fixed supply
    48/83

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  49. Bitcoin the protocol
    • stroke of genius, major disruptive invention
    replace any processing central authority with
    decentralized
    peer-to-peer
    cryptographically secure
    equivalent
    • This really is Web 3.0
    49/83

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  50. Smart Properties and Contracts
    • Smart properties are digital token that can be
    programmatically exchanged using smart
    contracts
    • Smart contracts are math (not legal) based
    contracts that do not need human interpretation
    or intervention to complete: the settlement is
    done by software.
    • Autonomous agents are software programs
    created for specific tasks: with Bitcoin they can
    now make and receive payments
    • Decentralized Autonomous Organizations
    50/83

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  51. No central authorities: examples
    digital tokens for:
    • Car ownership (car sharing)
    • Voting rights (liquid democracy)
    Distributed Autonomous Organizations:
    • Gambling online (no fees, no taxes)
    • Health insurance (without company costs)
    51/83

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  52. Proof of Existence
    • Block chain as time stamp authority
    • Put a hash value in the «comment» section of
    a (monetarily negligible) transaction
    • Hash being a fixed length string that uniquely
    identify an arbitrary length digital object (e.g.
    a txt or pdf file)
    • Existence of that digital object at the
    transaction time is proved on the block chain
    www.proofofexistence.com
    52/83

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  53. Bitcoin 2.0
    • Bitcoin-like block chains as public ownership
    database for digital assets
    • Meta-protocols: Namecoin, Mastercoin,
    Counterparty, ColoredCoins
    • Ethereum: next-generation smart contract and
    decentralized application platform
    53/83

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  54. Money as social relation instrument
    • Human beings are born into a gift economy
    • Enlarged relationship circle requires exchange
    economy
    • barter economy, coincidence of wants
    • trade economy, money as medium of
    exchange
    54/83

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  55. Information Economy
    • Mobile communication, Internet, and social networks
    • Cryptocurrency: money for the information economy
    55/83

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  56. Money Comparison
    Medium of
    Exchange
    Store of Value Unit of Account
    Live cattle
    Diamonds
    Gold
    Fiat coins and notes
    Cryptocurrency
    • swappable
    • fungible
    • portable
    • divisible
    • recognizable
    • resistant to
    counterfeiting
    • reliably saved,
    stored, and
    retrieved
    • retain usefulness
    over time
    • non-perishable
    or with low
    preservation cost
    • relative worth
    unit of measure
    • stable value for
    stable price
    comparison
    • supply must be
    limited in some
    way
    56/83

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  57. Money as value yardstick
    • Unit against which the value of every other
    good is measured
    • A good in itself: its value is governed by supply
    and demand
    • The price system measures the value of goods
    relative to the value of money
    • Good money should provide stable prices to
    best perform its role as unit of account
    57/83

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  58. Inflation and Deflation
    • reduction in the purchasing power per unit of
    money: money value decrease, price level
    increase
    • deflation hinders money’s unit of account role
    and encourages its hoarding. This can lead to
    perverse economic crisis.
    58/83

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  59. Monetary policy
    • delegated to central banks or equivalent
    monetary authorities
    • institutionally designed to be independents
    • central bank’s main objective is to safeguard
    the value of the national currency
    • low and stable rate of inflation is the implicit
    or explicit goal
    59/83

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  60. Statement of the Problem
    • The Bitcoin protocol has been successful at get rid of any
    centralized monetary authority
    • The bitcoin currency has inadvertently thrown away the
    flexibility of a fully automatic non-discretionary monetary
    policy allowing for elastic supply of money
    60/83

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  61. Transactions
    • Transactions/minute: 40-60 vs 200,000 VISA
    61/83

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  62. Friedrich Hayek
    Denationalisation of Money
    • history of coinage is an almost uninterrupted story of
    debasements; history is largely a history of inflation
    engineered by governments for their gain
    • why government monopoly of the provision of
    money is regarded as indispensable? It deprived
    public of the opportunity to discover and use a
    better reliable money
    A Free-Market Monetary System
    Lecture delivered at the Gold and Monetary Conference, New Orleans, Nov. 1977
    https://mises.org/daily/3204
    Denationalisation of Money-The Argument Refined, Third Edition
    The Institute of Economics Affairs 1990
    http://mises.org/books/denationalisation.pdf
    62/83

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  63. Analysis of the Theory and Practice
    of Concurrent Currencies
    • Commercial banks issue their own money:
    – Keep the purchasing power constant
    – Competition between currencies
    Blessed will be the day when it will no longer be
    from the benevolence of the government that
    we expect good money but from the regard of
    the banks for their own interest
    63/83

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  64. Fixed USD Exchange Rate
    • USD/BTC: 15-Apr-11 1.0, 29-Mar-14 500.0
    • x500 increase for BTC demand relative to USD
    • 29-March-14: 12.5M bitcoins in circulation
    • Inflate their number 500 times to 6250M
    • On 29-Mar-14 it would have been equivalent
    – to own 1BTC worth 500USD
    – or 500BTC each worth 1USD
    64/83

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  65. Rebasing Process Reaction Lag
    Daily rebasing
    65/83

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  66. Inflation adjusted USD
    • Adopting the USD Consumer Price Index
    • 6% inflation in the period March 2011-2014
    1.06
    66/83

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  67. Brent-Wheat Commodity Price Index
    67/83

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  68. Brent-Wheat Commodity Price Index
    68/83

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  69. Brent-Wheat Commodity Price Index
    69/83

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  70. Brent-Wheat Commodity Price Index
    70/83

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  71. Gold Commodity Price Index
    71/83

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  72. Gold Commodity Price Index
    72/83

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  73. Hayek Money
    The cryptocurrency monetary standard of
    elastic fully automatic non-discretionary supply
    regulated to achieve stable prices
    with respect to a (commodity) price index
    73/83

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  74. Seigniorage Shares
    • The perceived potential of a cryptocurrency as investment
    asset leads to hoarding and limited transaction volume
    • Shield coin holders from the direct effects of monetary
    phases, restraining monetary policy’s costs and benefits to
    holders of seigniorage shares
    • Seigniorage shares are a participation in a distributed
    central bank: owners are entitled to seigniorage revenues
    in exchange for being subjected to the losses associated to
    coin price stability defence, obliged to validation task
    duties, and in charge of price index observation
    • Free coins from any speculative value, thus favoring money
    velocity and increasing the number of transactions
    74/83

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  75. Two Monetary Digital Tokens
    • Two species of digital tokens: coins and shares. Block
    chain technology tracks ownership and transactions for
    both.
    • Coins are divisible, shares are not. Both can be used for
    transactions even if not fungible
    • Coins are minted as share dividends and distributed to
    shareholders
    • The right to validate transactions is reserved to
    shareholders, so here miner is a synonym of
    shareholder.
    • Miners are rewarded with the issuance of new shares.
    75/83

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  76. The Distributed Central Bank
    • Seigniorage shares are a participation in a distributed
    central bank
    • Owners are entitled to seigniorage revenues in
    exchange for being:
    – subjected to the losses associated to coin price stability
    defense
    – obliged to validation task duties
    – In charge of price index observation
    – network security, node synchronization, etc.
    • Shares are cryptographically identifiable, so those
    involved in double spending attempts are invalidated
    and “burned” away
    76/83

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  77. The Coin and Share Prices
    • The coin is actively pegged to a price index in
    order to make its value essentially constant at
    parity
    • Share price instead is free to float:
    expectations about expansionary monetary
    phases increment it, while contractionary
    phases depress it.
    77/83

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  78. Monetary Base
    • shares and coins in circulation, with prices
    and

    respectively,
    ≅ 1
    • The share market cap and the coin market cap add up
    to the overall outstanding monetary base:
    = ∙
    + ∙
    • Share market cap is the estimation of future coin
    issuance: assuming zero interest rate ∙

    is the
    expected number of coins to be issued in the future
    • The monetary base coin equivalent is:
    = ∙

    +
    = ∙
    78/83

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  79. Burning Coins for Shares
    • New shares can be issued at every block in exchange for a
    minimum auction price of

    burned coins
    • If no shares are bought in a block, in the next one the share
    auction price will be lowered. If shares are bought in a
    block, then the share auction price will be increased
    • The auction is not really depriving shareholders of value:
    assuming constant in an equilibrium state, the reduction
    of coin monetary base will just shift value in the share
    monetary base.
    • Only the coin price
    must be obtained exogenously to the
    network, relying on shareholders for its observation
    79/83

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  80. Price Index Deflation

    > 1, fresh new coins are minted and paid
    as share dividends.
    • This limits the appreciation potential of
    , as
    for a given coin market cap value ∙
    , the
    number of coins increases depressing
    .
    • As long as
    > 1 the share price is obviously
    non-negative
    > 0, as coins are expected to
    be paid as dividend.
    80/83

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  81. Price Index Inflation

    < 1, no dividends are expected on short-term: shares lose value

    is always incorporating the expectation of future coins “stored”
    into the market share price, so as soon as
    decreases then less
    future coins are expected and
    will experience a pull to parity
    proportional to the share market cap loss.
    • the share defensive help is exhausted when
    approaches zero.

    < 1 and
    > 0: price stability might be still defended if the
    market will consider further share devaluation enough to restore
    parity;

    ≅ 0 and
    > 0: this is the realization of the bitcoin case, with
    shares being equivalent to bitcoins

    < 1 and
    ≅ 0: price stability cannot be preserved unless coins
    are burned;

    ≅ 0 and
    ≅ 0: the cryptomoney is dead
    81/83

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  82. Bibliography
    • Hayek, F. A. (third edition 1990, first edition
    1977), Denationalisation of Money - The
    Argument Refined, The Institute of Economic
    Affairs, mises.org/books/denationalisation.pdf
    • Dowd, K. (2014), New Private Monies: A Bit-
    Part Player?,
    http://www.iea.org.uk/publications/research/
    new-private-monies-a-bit-part-player
    82/83

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  83. Bibliography
    • Ametrano, Ferdinando M. (2014), Hayek Money:
    the Cryptocurrency Price Stability Solution,
    http://ssrn.com/abstract=2425270
    • Ametrano, Ferdinando M. (2014), Price Stability
    Using Cryptocurrency Seigniorage Shares,
    http://ssrn.com/abstract=2508296
    • Sams, Robert (2014), A Note on Cryptocurrency
    Stabilisation: Seigniorage Shares,
    https://github.com/rmsams/stablecoins/blob/ma
    ster/00-main.pdf
    83/83

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