R help - Nov 2007 - cronbach's alpha

hie 
    1...i'm trying to carryout a relibility testusing cronbach's alpha
what fuctin do i use.
    
    2.. this is more of a statistical question.if the alpha value  for all the
variables  is negative what does it mean. and if the  alpha value is negative
for all tyha variables but is greater than 0.7  for some sections of the
variables what does that mean
  
  thanks in advance
  
  
       
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alpha.scale (psych)
cronbach (multilevel)

On Nov 14, 2007 7:33 AM, raymond chiruka <rtchiruka at yahoo.com>
wrote:
> hie
>     1...i'm trying to carryout a relibility testusing cronbach's
alpha what fuctin do i use.
>
>     2.. this is more of a statistical question.if the alpha value  for all
the variables  is negative what does it mean. and if the  alpha value is
negative for all tyha variables but is greater than 0.7  for some sections of
the variables what does that mean
>
>   thanks in advance
>
>
>
> ---------------------------------
> Never miss a thing.   Make Yahoo your homepage.
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>


-- 
CH Chan
Research Assistant - KWH
http://www.macgrass.com

look also at functions cronbach.alpha() and descript(), in the 'ltm' 
package.

Best,
Dimitris

----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://med.kuleuven.be/biostat/
     http://www.student.kuleuven.be/~m0390867/dimitris.htm


----- Original Message ----- 
From: "raymond chiruka" <rtchiruka at yahoo.com>
To: "r" <r-help at stat.math.ethz.ch>
Sent: Wednesday, November 14, 2007 12:33 AM
Subject: [R] cronbach's alpha

> hie
>    1...i'm trying to carryout a relibility testusing cronbach's 
> alpha what fuctin do i use.
>
>    2.. this is more of a statistical question.if the alpha value 
> for all the variables  is negative what does it mean. and if the 
> alpha value is negative for all tyha variables but is greater than 
> 0.7  for some sections of the variables what does that mean
>
>  thanks in advance
>
>
>
> ---------------------------------
> Never miss a thing.   Make Yahoo your homepage.
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide 
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
> 

Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm

alpha(psychometric) ?  
--- raymond chiruka <rtchiruka at yahoo.com> wrote:
> hie 
>     1...i'm trying to carryout a relibility
> testusing cronbach's alpha what fuctin do i use.
>     
>     2.. this is more of a statistical question.if
> the alpha value  for all the variables  is negative
> what does it mean. and if the  alpha value is
> negative for all tyha variables but is greater than
> 0.7  for some sections of the variables what does
> that mean
>   
>   thanks in advance
Could be several things but you may just have a coding
problem.  Is there any chance you have reversed your
coding of some items?