[gnaritas]

> Many very smart people have tried to model and then beat the market, and (apart from chance outcomes) no one has succeeded in the sense that they located a reliable, describable "method" for it.

That's an easy claim to make when you simply dismiss anyone who succeeds as random chance.

> by publishing the system he would destroy its effectiveness

Obviously and not disputed.

> I can use a computer to model a random market and random investors, using random price changes and random trades, and not surprisingly, half the investors will do better than the average outcome. What is surprising is that, when the above-average investors are humans, they invariably try to claim this chance outcome resulted from a winning system that they will sell to you for some princely sum.

That's not damning evidence, merely circumstantial.

> Yes, but there's a qualitative difference between "hard" and "impossible".

Yes there is, however I don't believe it's been adequately proven to be impossible.

[lutusp]

> That's an easy claim to make when you simply dismiss anyone who succeeds as random chance.

I never said this anywhere. You're confusing the practice of science with a blanket statement I never made. Pretend to be a scientist -- prove me wrong. Locate where I said what you claim I said.

> Yes there is, however I don't believe it's been adequately proven to be impossible.

Oh, great -- "proven to be impossible". Before you go on, learn about the impossibility of proving a negative:

http://en.wikipedia.org/wiki/Russell's_teapot

Quote: "Russell's teapot, sometimes called the celestial teapot or cosmic teapot, is an analogy first coined by the philosopher Bertrand Russell (1872–1970) to illustrate that the philosophic burden of proof lies upon a person making scientifically unfalsifiable claims rather than shifting the burden of proof to others ..."

Remember -- all I have ever said is that the possibility of a chance outcome cannot, must not, be dismissed, and to a scientist, it is the first possibility to be considered, not the last.

> That's not damning evidence, merely circumstantial.

What? According to the scientific rules of evidence, the burden of evidence is not mine to prove that a winning stock picking strategy does not exist (i.e. prove a negative), the burden is on others to prove that it does.

[gnaritas]

> I never said this anywhere. You're confusing the practice of science with a blanket statement I never made.

Poorly worded, I wasn't claiming you said it, I was saying you could claim it and you would because you consider it the null hypothesis.

> Before you go on, learn about the impossibility of proving a negative:

I don't need to research Russell's teapot, I'm well aware, that was a poorly thought out statement on my part is all. I didn't mean to ask you to prove a negative.

> Remember -- all I have ever said is that the possibility of a chance outcome cannot, must not, be dismissed, and to a scientist, it is the first possibility to be considered, not the last.

It's not being dismissed. The issue is whether it's just chance; that Buffet's disciples have also done consistently well disputes the null hypothesis. Please actually read what Buffet has to say[1], he's not stupid and he's not ignoring the null hypothesis.

[1] http://www.businessinsider.com/warren-buffett-on-efficient-m...