quinta-feira, dezembro 30, 2010

Outra Torre de Babel à espera de cair

Li duas vezes o artigo "Algorithms Take Control of Wall Street". Alguns sublinhados acerca desta espécie de Skynet:
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"The machines aren’t there just to crunch numbers anymore; they’re now making the decisions.
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That increasingly describes the entire financial system. Over the past decade, algorithmic trading has overtaken the industry. From the single desk of a startup hedge fund to the gilded halls of Goldman Sachs, computer code is now responsible for most of the activity on Wall Street."
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Isto faz-me logo recordar o funil de Roger Martin:
Algoritmo que no fim é transformado em código de programa informático.
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"(By some estimates, computer-aided high-frequency trading now accounts for about 70 percent of total trade volume.) Increasingly, the market’s ups and downs are determined not by traders competing to see who has the best information or sharpest business mind but by algorithms feverishly scanning for faint signals of potential profit.
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Algorithms have become so ingrained in our financial system that the markets could not operate without them."
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Depois, algo do tipo Torre de Babel "Oh! Reparem como nós somos poderosos!":
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"It is also harder to understand, predict, and regulate. Algorithms, like most human traders, tend to follow a fairly simple set of rules. But they also respond instantly to ever-shifting market conditions, taking into account thousands or millions of data points every second. And each trade produces new data points, creating a kind of conversation in which machines respond in rapid-fire succession to one another’s actions. At its best, this system represents an efficient and intelligent capital allocation machine, a market ruled by precision and mathematics rather than emotion and fallible judgment" (Moi ici: "intelligent capital allocation machine" ... mas existe tal coisa? Há cerca de 3 horas @EskoKilpi escreveu no twitter "Then the system is not complex :-) RT @ilparone: "When one can predict with reliability what is going to happen in a complex system... "". Exactamente um acidente à espera de acontecer...)
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"But at its worst, it is an inscrutable and uncontrollable feedback loop. Individually, these algorithms may be easy to control but when they interact they can create unexpected behaviors—a conversation that can overwhelm the system it was built to navigate. On May 6, 2010, the Dow Jones Industrial Average inexplicably experienced a series of drops that came to be known as the flash crash, at one point shedding some 573 points in five minutes." (Moi ici: estava online quando tal sucedeu. Uso os gráficos desse dia para ilustrar a esquizofrenia interpretativa do desempenho das organizações. O primeiro noticiário radiofónico que explicou o sucedido avançou com 3 justificações: as declarações de Trichet (em Lisboa nesse dia); a situação na Grécia, e as eleições ingleses que ocorreriam dias depois)
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"“Automated trading systems will follow their coded logic regardless of outcome,” she told a congressional subcommittee, “while human involvement likely would have prevented these orders from executing at absurd prices.” Delaware senator Ted Kaufman sounded an even louder alarm in September, taking to the Senate floor to declare, “Whenever there is a lot of money surging into a risky area, where change in the market is dramatic, where there is no transparency and therefore no effective regulation, we have a prescription for disaster.”
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That’s a tacit admission that the system has outgrown the humans that created it. Today a single stock can receive 10,000 bids per second; that deluge of data overwhelms any attempt to create a simple cause-and-effect narrative."
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Como é que se dá cabo de um algoritmo? Como é que se faz para que vire obsoleto?
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Voltando ao mistério e re-explorando-o, pondo em causa certezas que ficaram materializadas em regras heurísticas e que depois ficaram impregnadas nos algoritmos.
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O que é a biodiversidade da vida senão a confirmação de que não há algoritmos seguros e únicos.
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Esta gente é tôla.

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