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Evidence can be strong or weak. Every positive study result is evidence of presence, usually strong evidence. Every negative study result is evidence of absence, usually very weak evidence.
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That's not right, a negative study often still can give evidence that something is true, but it just didn't meet the p=.05 threshold.

p<=0.05 is so easy to achieve for actual positive results (just increase sample size) that I don't think it's productive to treat any result with p>0.05 as positive evidence for any purpose other than deciding to rerun the study with a bigger sample size.

And yet, people can be extremely vigilant about a positive correlation when it doesn’t fit their personal agenda, going as far as questioning methodology in even the least pragmatic ways possible; or, become accepting of the absence of evidence as evidence of absence when weak/no correlation is convenient to their own biases.

I'd say it's very sensible to assume absence up front before there's convincing evidence of presence. Sure, personal biases influence our evidence thresholds a lot, and often people demand unfair rigor that cannot be practically met. But the opposite is also true - sometimes people will believe in presence with zero evidence if they like it enough. The latter is far, far more dangerous than the former.

It’s one thing to believe in presence with zero evidence, and another to _withhold_ judgment when there’s zero evidence. I think you may be conflating the two.

Then again, perhaps we are simply two different types of people. I don’t believe that a complex system can be expected to stay the same when you introduce a new factor into it, while you prefer to adjust much later when effects appear or when evidence achieves total infallibility up to the academic level. I am risk-averse, you like taking it; I’d rather prevent, you’d rather cure. Stating that the former is “far, far more dangerous” is just begging the question though.




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