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Robin · 7th September 2008, 05:34 PM

A series of experiments by Dean Radin and others purport to show that the human mind reacted precognitively to stimuli.

The basic design of these experiments is that people are shown, in a random order, a series of photographs - some provoking a strong emotional reaction, some not. Skin conductance is measured both before and after and the results seem to show that dermal activity is higher when the emotional provoking is shown, both before and after the photograph is actually displayed. See Electrodermal Presentiments of Future Emotions for example. In some experiments MRI is used.

I decided to see if these results could be explained by an anticipation effect based on the photographs previously seen. It turns out they can.

The simulation produces 10 seconds worth of data and randomly chooses a state 1 or 0 after the first 5 seconds - representing "emotional" and "calm". The data in the first half of the run is influenced by variables based on past states, the second half is influenced by a function simulating an emotional reaction. A purely random number is also generated to simulate noise.

And yet when data from a series of tests is aggregated, it appears that there is a difference both before and after the random number is actually generated.

Compare with Radin's results.

So is my program precognitively sensing the random number chosen?

As it happens there is nothing mysterious or spooky happening here. I am increasing the anticipation factor if the previous state is "calm" and decreasing it when the previous state is "emotional". This means that whenever there is a run of "calm" the first "emotional" is guaranteed to be a local maximum, similarly the first "calm" after a run of "emotional" data will be a local minimum.

This produces a series of outliers that influence the aggregate result. When the "experiment" is run 20 times it produces a "presentiment" effect more than half of the time, the rest have no significant difference.

This would be consistent with, for example, a mounting anticipation effect after a series of calm-inducing photos and a slight desensitisation during emotion-provoking photos.

This appears to suggest that the presentiment experiments cannot be considered evidence for pre-cognition, paranormal activity or psi.

Just an interesting mathematical illusion.

Here is a link to the Source code

And here is a link to 20 consecutive runs of the program:

http://picasaweb.google.com.au/robin1658/Presentiments#

7th September 2008, 05:34 PM	#1
Robin Penultimate Amazing Join Date: Apr 2004 Posts: 14,971	Simulating "Presentiment" Experiments A series of experiments by Dean Radin and others purport to show that the human mind reacted precognitively to stimuli. The basic design of these experiments is that people are shown, in a random order, a series of photographs - some provoking a strong emotional reaction, some not. Skin conductance is measured both before and after and the results seem to show that dermal activity is higher when the emotional provoking is shown, both before and after the photograph is actually displayed. See Electrodermal Presentiments of Future Emotions for example. In some experiments MRI is used. I decided to see if these results could be explained by an anticipation effect based on the photographs previously seen. It turns out they can. The simulation produces 10 seconds worth of data and randomly chooses a state 1 or 0 after the first 5 seconds - representing "emotional" and "calm". The data in the first half of the run is influenced by variables based on past states, the second half is influenced by a function simulating an emotional reaction. A purely random number is also generated to simulate noise. And yet when data from a series of tests is aggregated, it appears that there is a difference both before and after the random number is actually generated. Compare with Radin's results. So is my program precognitively sensing the random number chosen? As it happens there is nothing mysterious or spooky happening here. I am increasing the anticipation factor if the previous state is "calm" and decreasing it when the previous state is "emotional". This means that whenever there is a run of "calm" the first "emotional" is guaranteed to be a local maximum, similarly the first "calm" after a run of "emotional" data will be a local minimum. This produces a series of outliers that influence the aggregate result. When the "experiment" is run 20 times it produces a "presentiment" effect more than half of the time, the rest have no significant difference. This would be consistent with, for example, a mounting anticipation effect after a series of calm-inducing photos and a slight desensitisation during emotion-provoking photos. This appears to suggest that the presentiment experiments cannot be considered evidence for pre-cognition, paranormal activity or psi. Just an interesting mathematical illusion. Here is a link to the Source code And here is a link to 20 consecutive runs of the program: http://picasaweb.google.com.au/robin1658/Presentiments#
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