Message-ID: <5892ec2d-5b9f-ef6a-e217-17333f2ce3e0@imbi.uni-freiburg.de>
Date: 2021-01-06T19:06:17Z
From: Gerta Ruecker
Subject: [R-meta] Inverting negative correlations
In-Reply-To: <CABvpDqnZq2ZNnG1C1Yp=VYarcFbFHA6hxRQxccCXCQ20S=XWrw@mail.gmail.com>
Dear David,
Yes, this is correct because
Cov(X,-Y) = - Cov(X,Y)
and the same holds for the correlations.
It is important that the wording is correct. For your example, the
interpretation would be that if there is a negative correlation between
social anxiety and extraversion, there is a positive correlation between
social anxiety and intraversion.
Best,
Gerta
Am 06.01.2021 um 19:50 schrieb david detullio:
> Hello all, I want to include correlation coefficients in a random-effects
> model for meta-analysis. If the majority of the correlations are positive,
> could I use the absolute values of any negative correlations if such
> correlations would have been positive had one of the measures been reverse
> scored? As an example, say there is a negative correlation between a
> measure for social anxiety and a measure for extraversion. Would it be
> possible to take the absolute value of the correlation under the assumption
> that the correlation would be positive if the measure for extraversion was
> reverse scored? Any answers would be appreciated, and if anyone knows of
> source material that talks about this process, the reference would be
> appreciated as well.
>
> [[alternative HTML version deleted]]
>
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