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141 lines
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********************
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Quantopian Manifesto
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********************
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Wall Street's culture was born in an age of information scarcity.
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Hoarding information and keeping secrets were the norm. The world has changed.
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Today's world is defined by information that wants to be free. The new
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scarcity is people: people with the talent and drive to wring insight from all
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of that data.
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Quantopian's mission is to attract the world's algorithmic and
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financial talent. We want to attract today's quants, and we want to
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attract talent that hasn't yet had the opportunity to be a quant. We
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want to bring this talent together, provide them with the tools that they
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require, and help them build a community. First and foremost, our community is
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rooted in openness and sharing. Members share code, know-how, and data.
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Quantopian sets the tone by providing open-sourced code, discussing our
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techniques, and supplying the historical data needed for algorithmic investing.
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By educating more people about statistical arbitrage and data mining for
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finance, we aim to dispense with the secrecy and raise the state of the art.
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Rather than hoard data, we relentlessly push data to our community. We want to
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diversify the data that can be mined, and permit our members to explore as much
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as they like. Our members' success in analyzing and investing will help
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us draw more data and more members to our community. Every individual's
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success will also help other Quantopians.
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The Evolution of Algorithmic Finance
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====================================
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Charting
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--------
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Algorithmic finance originated as chart reading. Chartists would look for
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certain patterns in price history charts. The patterns were always graced with
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artfully chosen names like 'head and shoulders,' 'spinning top', or 'morning
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star'. Chart reading looks a lot like palm reading, and for the skeptics among
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us the similarities don't end with appearances. Still, chart reading is an
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attempt to infer the balance of buying and selling appetites in the markets
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from a stock's history. Viewed that way, chart reading pursues the noble goal
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of prediction. Charting is so common that certain events can trigger market
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responses, possibly because so many participants infer the same meaning from a
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stock's price chart.
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Technical Analysis
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------------------
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Analysis grew more sophisticated as chartists gave way to
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computer scientists writing algorithms. These algorithms have more scientific
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sounding names like Moving Averages, Volume Weighted Moving Averages, Bollinger
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Bands, Relative Strength Indicators, and Pearson's Correlation
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Coefficient. Building technical analysis algorithms looks a lot like modern
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statistics, and the optimists among us would say the similarities run deep.
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Technical analysts take algorithmic approaches to the same concept: inferring
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future behavior from trailing data. In addition to greater sophistication,
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technical analysts can also test their algorithms over historic data. Imperfect
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to be sure, but a giant leap from staring at a chart.
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Reasonable people can disagree about the 'correctness' of
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inferring future events from past behavior. Rather than dwell on that question,
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we choose to point out a different limitation of both charting and modern
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technical analysis: **both interpret the movement of a single stock in
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isolation**. This limitation is both a blessing and a curse.
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On the one hand, there is little room for sophisticated statistics or machine
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learning when you have just a single time series for both your signal and your
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prediction target.
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On the other, technical analysis can still be intuitive, which makes it easier
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to get acquainted with the idea of automated trading. Often there is a mental
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leap for people to make from understanding the interpretation of a price series
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to issuing orders. Because the signals are easy to understand, technical
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analysis makes for a good initial learning experience to explore risk and
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performance evaluation as well as order management: the price going above its
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30 day moving average is something you can visualize. So, you can focus your
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attention on the financial and trading aspects of the problem.
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Statistical Arbitrage
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---------------------
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Statistical Arbitrage is the grandchild of chart reading.
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Like technical analysis it relies on algorithms and statistics, but it departs
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in one very significant way: 'stat arb' looks for relationships
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among many stocks. The challenge with stat arb is twofold:
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* visualizing the relationships can be quite difficult, since the relationships
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can have high dimensionality
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* the data processing load is quite high - a simple linear regression for all
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stocks results in 32 million individual regressions. Assuming a 10-day
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window, that can be 320 million individual calculations. To prepare,
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backtest, and trade a stat arb strategy required both familiarity with the
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mechanics of trading, knowledge of statistics, and a strong computer science
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background.
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As stat arb matured, the competition to find stat arb strategies that work
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became a two part race:
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1. execute the trades faster
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2. find new ways to identify relationships within
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market data
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We think the pursuit of faster trades reached diminishing returns when the
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market hit sub-millisecond trade execution. We think that the resulting high
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level of liquidity is a good thing, but we agree with Thomas Petterffy that
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`pursuing even faster trades
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<http://www.npr.org/blogs/money/2012/08/27/159992076/a-father-of-high-speed-trading-thinks-we-should-slow-down>`_
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"has absolutely no social value".
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Finding new relationships in the market data is possible and more important now
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than ever. In the summer of 2007, there was a sudden meltdown in quantitative
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trading firms. Subsequent analysis points to quants crowding into the same
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arbitrage bets, and an unforeseen fund liquidation driving all the quants to
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unwind those bets concurrently. We believe finding new relationships should
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permit investments with lower correlation and lower risks.
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Algorithmic Investing and the Future
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====================================
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A revolution in market understanding happens next. We want Quantopian to enable
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more quants than all of Wall Street combined. We want quants, new and old, to
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explore and share new ways to view the market. We want to clear away the
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obstacles that have so far kept all but a few from doing algorithmic investing
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by:
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* simulating with clean, high-quality market data for free
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* easy access to markets through trusted brokers
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* providing a robust, flexible open-source backtester to permit evaluation and
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iteration of algorithms
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* supporting a community that fosters the exchange of knowledge, ideas, code
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solutions, and data sources
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The community will find new ways to identify market opportunities. It may take
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the form of new, non-market data sources, like news feeds or Twitter. It may be
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new algorithmic techniques. Most likely, it will be something we
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haven't heard of yet: your idea. The one you keep coming back to. The
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idea you couldn't test without data. The idea that needs backtesting,
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and iteration, and encouragement from other quants.
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Do you want to unleash your idea? This is your chance. `Come hack Wall Street
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<http://www.quantopian.com>`_.
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