R help - Oct 2009 - Johnson-Neyman procedure (ANCOVA)

Dear R users,

Does anyone know of a package that implements the Johnson-Neyman procedure -
for testing differences among groups when the regression slopes are
heterogeneous (in an ANCOVA model)? I did not get any matches for functions
when searching using R Site Search.

If it has not been implemented in R, does anyone know of another statistical
package that has this procedure? I found very old scripts available for
Mathematica, but have had difficulty getting them to work.

Thanks in advance.

best,

Steve
-- 
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On 10/30/2009 9:20 PM, Stropharia wrote:
> Dear R users,
> 
> Does anyone know of a package that implements the Johnson-Neyman procedure
-
> for testing differences among groups when the regression slopes are
> heterogeneous (in an ANCOVA model)? I did not get any matches for functions
> when searching using R Site Search.
> 
> If it has not been implemented in R, does anyone know of another
statistical
> package that has this procedure? I found very old scripts available for
> Mathematica, but have had difficulty getting them to work.
http://www.comm.ohio-state.edu/ahayes/SPSS%20programs/modprobe.htm
> Thanks in advance.
> 
> best,
> 
> Steve
-- 
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