Re:Markets are efficient if and only if P=NP (2010)
by ChrisLomont on Wednesday October 21, 2020 @10:17PM
(#24854295)
The complexity of factoring RSA keys is not known, so this method isn’t sufficient.
It is known on a quantum computer factoring is polynomially hard.
Re:Markets are efficient if and only if P=NP (2010)
by yowlingcat on Wednesday October 21, 2020 @10:26AM
(#24848176)
> The EMH is a framework. With any scrutiny it's obvious that it can at most be first order accurate since obtaining and processing information is costly. This is not a particularly new insight or one that would be a surprise to any proponent of the EMH.
Great clarification. I'm always suspicious of interpretations of EMH that are a lot more literal than they should be, drawing effectively false conclusions from double negations. I think the truth is as you said.
Re:Markets are efficient if and only if P=NP (2010)
by whatshisface on Wednesday October 21, 2020 @10:30AM
(#24848228)
>at most be first order accurate
The EMH is accurate to way better than the tangent line, which is what a first order approximation is.
Re:Markets are efficient if and only if P=NP (2010)
by murbard2 on Wednesday October 21, 2020 @08:53PM
(#24853915)
When someone says a consideration is orthogonal to another one, they are not literally embedded in an Euclidean space. In this context, first order is used loosely to mean that the deviations come from effects which are only secondary in magnitude and relevance, not to indicate that we're looking at the asymptotic behavior of a formula when a parameter is taken to be infinitesimal.
Re:Markets are efficient if and only if P=NP (2010)
by whatshisface on Thursday October 22, 2020 @10:14AM
(#24858231)
The trouble is that EMH is a formula, so the "to first order" thing has a literal meaning that is not what the author meant. It's kind of like saying that "1-x^2/2 is cos(x) to first order," moreso than saying "my business plan is a good idea for every involved party, to first order."
In fact, you can embed more powerful oracles like this, e.g. publicly traded company announces a $1,000,000 dollar prize for anyone who submits an inconsistent statement in ZFC.
The EMH is a framework. With any scrutiny it's obvious that it can at most be first order accurate since obtaining and processing information is costly. This is not a particularly new insight or one that would be a surprise to any proponent of the EMH.