Overly simply, the Arbitrage Pricing Theory presumes that there is in fact a "fair" price or market-clearing price for a given security. And that there's a linear equation that can accurately model and measure the "perfect price." Once it's measured, the arbitrageur (what a word!) will sell the overpriced stock and buy the underpriced one and get paid "risklessly" for adding intelligence and liquidity to the marketplace.
It's a concept. In reality, it's not something heavily relied upon. Too many variables in predicting any one CEO's tantrum-scandal which "changes everything."
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Finance: What is the Fast Market Rule?11 Views
Finance a la shmoop what is the fast market rule? okay things get crazy here [Two guys riding a rollercoaster]
whoa and every now and then there's a leap well blimey, that's how things work
here on the London Stock Exchange.....
the fast market rule accommodates the chaos by giving brokers and other market
makers the freedom to trade outside the ranges published to the exchange why is
this needed? well because we live in a world of robots and artificial
intelligence and fat thumbs that hit the wrong keys and hackers from Russia China
and Mars all of whom can profit from chaotic disruption if you want to see
this phenomenon in its finest form well check out Jack Nicholson in the original [Man stood next to Jack Nicholson as Joker]
Batman movie and that was the best one so the logic revolves around the fact
that today even with all our massive computing power we would still rather
rely on human beings when you know the congressman hits the fan then assume
that a computer will be clever enough to figure out what's wrong quickly you know
when the world is on a collision course with chaos all over the place fast [Meteor strikes Earth]
market rule, humans over robots...
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What is Arbitrage? Arbitrage is a trading strategy used to make risk-free money. The investor buys a security in one market and sells it in another...