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Could It Be? Spooky Experiments That 'See' The Future

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Re: Could It Be? Spooky Experiments That 'See' The Future

#91

Post by jeromec »

Encosia wrote: post #89
jeromec wrote: post #83

Earlier quoted context omitted.

For the "Who's got the porn" experiment I don't think test takers knowing which group they were in would make much difference. My understanding is that both groups would be told they were being tested for ESP. However, one group is told hot stimulating pictures are mixed in with regular pictures, and the other group is told there are only regular pictures. According to the article, the group with no added incentive (…

I agree that it shouldn't make any different, logically, but then your control group still isn't truly a control group. Your results could be doubted on the basis of things like the participants knowing too much about the experiment and trying to guess patterns in the RNG.

Oh, yes, any results we came up with running the experiment here should be properly doubted from the start. Not only would participants know too much about the experiment, but over the Internet participants wouldn't be directly observable which certainly throws out any real legitimacy. I was only thinking in terms of possibly recreating enough of the test to experience some of the same results, regardless of how those results might be perceived, but I think too much information about the test is now known.

Re: Could It Be? Spooky Experiments That 'See' The Future

#92

Post by phob »

beagle3 wrote: post #54
CWuestefeld wrote: post #24

Earlier quoted context omitted.

the more tests you do, the sooner you'll see a fluke on average In other words, if you toss a coin 1,000 times, then it's hideously unlikely that you'll see a run of 100 consecutive heads. But if you toss the coin 100,000,000 times, you shouldn't be too surprised to see that 100-toss run buried in there somewhere, even though the odds of getting 100 in a row are so small. Right?

Not really. If you toss 100,000,000 == 2 ^ 27, you should only expect around 30 in a row. To have a good chance of getting 100 in a row, you need about a billion squared times more. And the problem is MUCH worse than described above: Let's say you test 1000 wrong hypothesises with p=0.05; 50 of those will be accepted as true, even though all are wrong. If you test 980 wrong hypothesises and 20 right ones, more than h…

This is why we replicate studies. Unreplicated parapsychology results are a dime a dozen.

Re: Could It Be? Spooky Experiments That 'See' The Future

#93

Post by phob »

lukev wrote: post #27
ewjordan wrote: post #17

Earlier quoted context omitted.

It's simply the way Bayesian statistics work: if the prior probability of something happening is very low, then for me to flip from thinking "didn't happen" to "did" it will take some new information that is very powerful. If you think that's illogical, I'd ask you to consider why a teacher is more likely to accept the excuse "my dog ate my homework" than "aliens kidnapped me and stole it". You seem to be arguing tha…

This is true, but I'd add a caution: just because something seems outlandish or improbable doesn't mean it actually has a low prior probability. Human intuition on what's weird and what's not is not a reliable oracle of prior probability. If you're going to give the prior an actual number, you better base it on actual facts. In your example, based on existing data, it is indeed fair - some dogs do sometimes eat homew…

But we do have reasonable priors on parapsychology from its wasteland of unreplicated, flawed studies, with no convincing results despite decades of effort.

Re: Could It Be? Spooky Experiments That 'See' The Future

#94

Post by lallysingh »

mbrubeck wrote: post #58

Here is some very good discussion of (failed) attempts to replicate the study, and at least one possible methodological flaw that could invalidate some of the results: http://psychsciencenotes.blogspot.com/2010/11/brief-note-dar... "The real lesson? This is the level of methodological scrutiny every paper should receive, and not just the ones you think are crazy: the ones you like and rely on for your own work should…

I'm wondering if the real point of the paper is to point out how insufficient the experimental design & statistics used in its contemporaries.

Re: Could It Be? Spooky Experiments That 'See' The Future

#95

Post by endtime »

nl wrote: post #77
endtime wrote: post #60

Earlier quoted context omitted.

I suppose that's true, though if someone can intuit a crypto-strong PRNG then that's an interesting and significant result in itself.

Javascript random() isn't a crypto-strong PRNG. Depending on how any PRNG is seeded, guessing it's output may not be very hard at all - especially if you've seen it once before. Eg, I once had a Poker playing game on an Amstrad that used a PRNG with a very predicable seeding strategy. I could amaze my friends by knowing exactly what cards I would be dealt.

I'm not suggesting that JS's random() is crypto-strong. I was replying to this part:

>I think you need a true random number generator to truly test this

Re: Could It Be? Spooky Experiments That 'See' The Future

#96

Post by jordyhoyt »

Eliezer wrote: post #51
CWuestefeld wrote: post #24

Earlier quoted context omitted.

the more tests you do, the sooner you'll see a fluke on average In other words, if you toss a coin 1,000 times, then it's hideously unlikely that you'll see a run of 100 consecutive heads. But if you toss the coin 100,000,000 times, you shouldn't be too surprised to see that 100-toss run buried in there somewhere, even though the odds of getting 100 in a row are so small. Right?

Bad example. You just never get 100 heads in a row on a fair coin, period.

Eliezer, please explain this to me.

Re: Could It Be? Spooky Experiments That 'See' The Future

#98

Post by marze »

jordyhoyt wrote: post #96
Eliezer wrote: post #51

Earlier quoted context omitted.

Bad example. You just never get 100 heads in a row on a fair coin, period.

Eliezer, please explain this to me.

Elizer is probably assuming an actual coin. P for 100 heads in a row is 1 in 2^100 attempts, or 10e30. You wouldn't live long enough.

Re: Could It Be? Spooky Experiments That 'See' The Future

#99

Post by beagle3 »

phob wrote: post #92
beagle3 wrote: post #54

Earlier quoted context omitted.

Not really. If you toss 100,000,000 == 2 ^ 27, you should only expect around 30 in a row. To have a good chance of getting 100 in a row, you need about a billion squared times more. And the problem is MUCH worse than described above: Let's say you test 1000 wrong hypothesises with p=0.05; 50 of those will be accepted as true, even though all are wrong. If you test 980 wrong hypothesises and 20 right ones, more than h…

This is why we replicate studies. Unreplicated parapsychology results are a dime a dozen.

Who are "we"? Physicists are the only ones who still do as far as I can tell -- everyone else prefers to spend their research budget somewhere else.
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