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april 20, 2004
Figurer i molnen
I Skeptical Report-artikeln Shapes in the Clouds diskuteras och kritiseras den parapsykologiska forskningen kring Remove Viewing (klärvoajans), speciellt PEAR (Princeton Engineering Anomalies Research), ett av de mest berömda projekten .
Efter att diskutera statistiskt metodologi görs en mer lättfattligt analogi med hitta mönster/figurer i moln: om man letar aktivt efter mönster i en tillräckligt stor datamängd så finner man alltid något intressant. (Ett annat exempel vore att hitta mönster bland stjärnorna på stjärnhimmeln.)
It is now well documented that the human mind is capable of finding patterns in a huge variety of situations. In fact, it is actively seeking recognisable patterns in the environment, in an attempt to make sense of it, to take advantage of it. This particular subject is far larger than can be dealt with in this critique, and in any case it is has a lot of supporting evidence to support it. So I will concentrate on that subject with specific reference to PEAR's analyses of their data. The point being made here is that the human mind's search for patterns is innate to us as humans - we have this ability in us, and it is relentless - it is almost impossible for us to avoid the process.
With this in mind, consider these two actual and unretouched pictures of clouds, courtesy of CloudClub. Our human minds, in search of patterns, will almost inevitably find sufficient pattern information to define "a bunny" and "a dragon". (Although it would probably be more accurate to say that our Westernised minds would allow these definitions to come to the fore - other cultures do not have rabbits or dragons.)
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But consider the actuality of these cloud formations - what is really so about them - what is their data? Do they contain something actually physically different from any other clouds that make them form shapes recognisable to us? In all sensibility, any factors affecting cloud formation create clouds that are no different to the innumerable others that form all the time in our atmosphere. It is just that these particular ones look like a bunny and a dragon to us because the shapes are familiar to us. There is no reason or evidence to show that the formation of a "bunny cloud" or a "dragon cloud" is any more or less likely than the appearance any other shape of cloud. In reality, the shape we perceive is purely the result of a desire, a search-for-a-pattern, in the human mind, not any inherent property of the cloud formation itself.
So it is possible to say that in almost all cases, a pattern of some sort that we recognise can possibly be seen be seen in just about any ambiguous data situation. It would then be reasonable to conclude that such pattern seeking in the face of the ambiguity of the data will be an artifact and very highly subjective.
And this is what has happened with the PEAR data, and seems to fully explain the results they obtained. The initial "positive" effects were obtained as the result of some highly subjective and high-level judging of the data sets. This is the equivalent of seeing a shape in the clouds. But as the analyses were refined, the positive effects tended to be less visible, in the same way that the closer you look at any cloud, the less it looks like any recognisable shape at all. The ultimate result for PEAR was that the "final analyses" revealed no evidence in support of the initial positive results at all, the equivalent of getting down to droplet level in a cloud where its total shape becomes meaningless. In effect, the PEAR analyses changed from being subjective, with good results, to objective, with none.
In most situations, improved analysis of data will tend to magnify an effect, if it is there to be found. Refinement of the testing and analyses throws the focuses more and more on the reasons and/or components that create the positive effect, and they become magnified. However, if the effects tend to disappear with such refinement, it can be reasonably assumed that either the refined testing did not take all available data into account, or that the effects were imaginary or an artifact. PEAR sieved the whole 25 years' worth of data in this exercise, and used a number of methods of analysis to try to capture the intended effects, so all the available data was in play. Therefore it becomes a bit difficult to escape the conclusion, given their stated results, that PEAR were actually chasing something subjective - imaginary - from the outset.
In other words, there was never any RV [Remote Viewing] effect at all to be found. They just saw a bunny in the clouds!
Se även
The Skeptic's Dictionary-artikeln PEAR
samt
Littlewood's Law of Miracles -The law of truly large numbers
Statistisk data snooping - att leta efter sammanträffanden
Sammanträffanden.
Posted by hakank at april 20, 2004 09:48 FM Posted to Kognitiva illusioner | Sammanträffanden | Skepticism, parapsykologi etc