Date:         Tue, 4 May 2004 09:25:35 +0200
Reply-To:     Spousta Jan <JSpousta@CSAS.CZ>
Sender:       "SPSSX(r) Discussion" <SPSSX-L@LISTSERV.UGA.EDU>
From:         Spousta Jan <JSpousta@CSAS.CZ>
Subject:      Re: Reversal equation from z to r
Content-Type: text/plain; charset="iso-8859-2"

Hi Martin,

If I still remember the basics of calculus correctly :-) then

compute r = (exp(2*z)-1)/(exp(2*z)+1).

(Supposing z = .5*((ln(1+r))-(ln(1-r))).)


HTH

Jan

-----Original Message-----
From: Martin Sherman [mailto:MSherman@loyola.edu]
Sent: Tuesday, May 04, 2004 4:15 AM
To: SPSSX-L@LISTSERV.UGA.EDU
Subject: Reversal equation from z to r


Dear list;
The following equation converts a r into a z (Fisher's r to z). Does anyone know how I would reverse this equation. That is what would the equation be for converting a z into a r. TIA

compute z = .5*((ln(1+r))-(ln(1-.r))).

Martin F. Sherman, Ph.D.
Professor of Psychology
Loyola College
222 B Beatty Hall
4501 North Charles Street
Baltimore, MD 21210

410 617-2417 (Office)
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msherman@loyola.edu