**=========================================================================
****Date:** Mon, 31 Jul 2006 13:27:01 +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: Transforming into normal distro
**Content-Type:** text/plain; charset="US-ASCII"
Hi Marc,

The best possible try is to use normal scores RANK ... /NORMAL.

GET FILE='C:\Program Files\SPSS\Cars.sav'.
NPAR TESTS
/K-S(NORMAL)= weight
/MISSING ANALYSIS.
RANK
VARIABLES=weight (A) /NORMAL /PRINT=YES
/TIES=MEAN /FRACTION=BLOM .
NPAR TESTS
/K-S(NORMAL)= Nweight
/MISSING ANALYSIS.

But beware:
1) The transformation is generally very much non-linear and hard to
generalize
2) In some cases (discrete variables) it is impossible to obtain a
normal distribution even with this method.

Usually one rather tries "standard" transformations (log, 1/x, exp,
arctg...) to obtain something more Gaussian (even if not perfect
Gaussian) or uses non-parametric methods which does not require
normality.

Greetings

Jan

-----Original Message-----
From: SPSSX(r) Discussion [mailto:SPSSX-L@LISTSERV.UGA.EDU] On Behalf Of
Marc
Sent: Monday, July 31, 2006 1:13 PM
To: SPSSX-L@LISTSERV.UGA.EDU
Subject: Transforming into normal distro

Hello everybody.

I made the K-S test on the dependent variable and saw that it is not
normally distributed (Asymp. Sig. = 0,000).

Is there a data transformation or some magical incantation that exists
somewhere to transform this data into a normally distributed set ?

Bye,