Experimenter Effects in Mainstream Science
by Rupert Sheldrake
Most skeptics would agree with Michael Mussachia (Skeptical Inquirer Nov/Dec 1995)
that "our beliefs, desires and expectations can influence, often subconsciously,
how we observe and interpret things". In psychology and clinical medicine
these principles are widely recognized, which is why experiments in these subjects
are often carried out under blind or double-blind conditions.
In a double-blind clinical trial, for example, some patients are given tablets
of a drug and others are given similar-looking placebo tablets, pharmacologically
inert. Neither scientists nor subjects know who gets what.
How widespread are experimenter expectancy effects in other branches of science?
No one seems to know. I have attempted to quantify the attention paid to experimenter
effects in different fields of science.
See Papers on Experimenter Effects
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