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0 pointsmatheweis9y ago0 comments

> the stock market is a random walk with a meager trend upwards that doesn't beat inflation + trading costs.

That assumes that the efficient-market hypothesis holds true, but it has yet to be thoroughly proven or disproven... (and funds like Medallion would strongly suggest otherwise for the medium term: https://www.bloomberg.com/news/articles/2016-11-21/how-renai...)

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dandermotj9y ago· 2 in thread

It doesn't assume the Effiecient Market hypothesis - empirical studies of returns support random returns without the imposing a model (non-parametric tests).

That's not to say returns are actually random, but in any given time range, it appears to be.

matheweisOP9y ago

EMH and random walk theory are intrinsically linked; you can't have one without the other...

Or are you saying that movements aren't actually random, and only appear to be?

dandermotj9y ago

The latter

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