Ever search for evidence of absence instead of finding absence of evidence?
December 23, 2012 12:57 PM Subscribe
Is scientific research ever organized to search for evidence of absence by reversing the null hypothesis? If not, why not?
posted by nathan v to science & nature (5 answers total) 5 users marked this as a favorite
It occurs to me that I can't think of any studies that do so, and that in the fields in which I'm interested (mostly medicine), people instead reject a hypothesis only after one or more published studies have failed to find a statistically significant correlation. Is there validity in rejecting hypotheses based on (repeated?) failure to find positive results, rather than choosing a correlative relationship as the null hypothesis?
I can imagine that, in many fields, you wouldn't want to set up research this way because you end up with a weak conclusion, but then I can imagine other research where a weak conclusion might be all that they can get (like, say, studying homeopathy).
Do many studies include enough raw data that they could be reinterpreted with a reversed null like this? Are there some reasons why reinterpreting the data would be an invalid way to do an experiment? If not, wouldn't it be a good idea for somebody to do some meta-research with these reversed nulls, to for instance say something stronger about the ineffectiveness of something like homeopathy?