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0 pointsAaronFriel6y ago0 comments

This is taken as axiomatic by people who believe in the efficient market hypothesis, but I don't think there's much reason to believe it's true.

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etrk6y ago

This isn't new technology. SiBeam came out of Berkeley Wireless Research Center in the mid-2000s. They had mmWave phased arrays from the start (60 GHz is pretty much useless without a phased array, or a large dish antenna if you're outdoors), but in 15 years, they never managed to find a compelling consumer use case.

I think at that point, the burden is on the company to prove its value.

SAI_Peregrinus6y ago

The efficient market hypothesis implies that P==NP. There's a LOT of reason to believe it's false.

vba6y ago

How so? Can you elaborate? Genuinely interested

aesthesia6y ago

Well, a naive, overly strong formulation of the efficient markets hypothesis may imply that P=NP. Something like "an optimal trading strategy is a function depending on the entire market history, and in order to find an optimal trading strategy, one must check an exponentially large space of such functions."

The paper is here: https://arxiv.org/pdf/1002.2284.pdf. They do a sketchy reduction to an extremely stylized model of the market from the knapsack problem and 3-SAT.

sudosysgen6y ago

Here is a paper on it : https://arxiv.org/pdf/1002.2284.pdf

novok6y ago

Google 'likelihood of P = NP' or 'efficient market hypothesis P = NP'

bordercases6y ago

Rather than using the metaphors from one field in another field whose day-to-day has little to do with those concepts, try reading a book:

https://www.amazon.com/Efficiently-Inefficient-Invests-Marke...

variaga6y ago

Even if the EMH were true, it only says "_IF_ a market is efficient, THEN all <modifier depending on the EMH version> information is included in the price."

The EMH does not imply that any particular market is efficient, and if the market isn't efficient, the EMH doesn't apply.

Lots of people do appear to assume the axiom "All markets are efficient", but that is plainly incorrect.

perl4ever6y ago

I think there was some nobel prize winning refinement to the theory that basically said markets approach theoretical efficiency in the limit as transaction costs go to zero, and interesting deviations from efficiency happen because transaction costs are not zero. Like, the whole reason we have firms and markets in real life is because zero transaction costs don't exist globally and so it helps to have ways to reduce them here and there.

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