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by bdjsiqoocwk 633 days ago
There's various versions, usually named weak version, strong and strongest. I don't remember which one is which, but the one I find interesting is "all publicly[1] available information is already incorporated into the prices". This is not a statement of absolute certainty but a statement on expected values. The reason I said your claim is dumb is that it's equivalent to "EMH says there's no infinite free money". I'm pretty sure everyone agrees there's no infinite free money, that's so obvious we don't even give a name to that hypothesis.

[1] how to define what publicly means exactly is also a question on itself which is important but not theain point here.
1 comments
echoangle 633 days ago
But „all publicly available information is already incorporated into the prices“ is exactly the reason why there’s no free money. It means that any difference between expected value based on new information is immediately arbitrated away and the actual value adjusts.
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bdjsiqoocwk 633 days ago
> and the difference you’re arbitraging isn’t decreasing

You literally said this, which means _infinite_ capacity. But now you're omitting that.

So what I'm reading is that your position is "EMH can only be falsified if someone finds infinite free money". Alright, this is what I call the church of the Efficient Market.

I don't know if you're trolling or just ignorant. I'm leaning towards trolling. Either way I've lost interest the conversation.

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echoangle 633 days ago
I am seriously not trolling, I’m just not sure how EMH is even controversial.

I also don’t get what I’m omitting. If you have an arbitrage opportunity, EMH means that this opportunity will disappear over time because the information that the opportunity exists spreads around and the opportunity is used up. That’s why EMH would mean that you can’t make infinite free money by arbitrating the differences. That’s what I meant and I still stand by it.

> So what I'm reading is that your position is "EMH can only be falsified if someone finds infinite free money"

Basically yes, and I’m not expecting EMH to be disproven because it’s pretty obvious.

What else would contradict the pretty basic claims of EMH?

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