Date: Wed, 24 Aug 2005 17:49:05 +0100
Sender: "SPSSX(r) Discussion" <SPSSX-L@LISTSERV.UGA.EDU>
From: Keith Starborn <firstname.lastname@example.org>
Subject: Re: reversing z scores
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In order to reverse the direction of a z score, you can either:
(1) multiply the old Z score by -1 so NEWZ = (-1 * OLDZ)
(2) subtract the old z score from 0 so NEWZ = (0 - OLDZ)
Quoting sarai batchelder <email@example.com>:
> Hi all,
> this seems like it should be simple but I can't figure it out.
> I have a variable that I want to convert into z-scores, but I want
> the order to be reversed. The problem is that I have a series of
> scales of neuropsych functioning that I want to make into z-scores
> and then average, but "good scores" are high on some scales and low
> on other scales. How to make z-scores that are all interpreted in
> the same direction, so that an average is meaningful?
> Sarai Batchelder
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