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Re: [LUG] OT - placebos

 

On Sat, Dec 19, 2009 at 04:54:01PM +0000, Neil Williams wrote:
> 
> Placebo is just another name for operator bias. Bias occurs whenever
> anyone involved in making the judgement have any knowledge of what has
> changed between the various times at which a judgement is made. Bias is
> unavoidable; you can only compensate for it, never avoid it.
> 
> Placebo != imagination
> Bias != imagination
> 
> The placebo effect and operator bias are absolutely real effects,
> statistically measurable and completely unrelated to imagination.
> 
> Science has proved again and again that if the judgement is made with
> knowledge of when the change was made, the judgement will reinforce the
> beliefs of those making the judgement with a statistically significant
> effect.
> 
> Double-blind randomised trials are the only rigorous method of
> compensating for the ever present placebo effect, no amount of bluff
> and blustering will change the reality.
> 

See 
http://en.wikipedia.org/wiki/Placebo
http://www.bbc.co.uk/science/horizon/2002/homeopathy.shtml

Getting a truly double blind randomised result that is statistically
significant takes a great deal of effort.

Another example of this "placebo" effect is in finance and is why the
FSA insist on a clause such as "past performance is no guide to future
returns". 

http://www.moneymadeclear.fsa.gov.uk/products/investments/types/pooled_investments.html


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