[R] Re:a more specific question about qda

[Daniel Amorèse]

Le 2002.05.22 16:25, "Huntsinger, Reid" a écrit :
> This measure of "discriminatory power" is derived from linear, not
> quadratic, discriminant analysis. Univariate QDA can discriminate between
> normal distributions with equal means but different variances. 
> 
> help(qda) suggests that the "means" component and the "scaling" component
> of
> the return are most of what you're looking for.
> 
> Reid Huntsinger
> 
> -----Original Message-----
> From: Daniel Amorèse [mailto:Daniel.Amorese at geos.unicaen.fr]
> Sent: Wednesday, May 22, 2002 9:07 AM
> To: r-help at stat.math.ethz.ch
> Subject: 
> 
> 
> Perhaps, I should complement my previous e-mail question:
> I am trying to select variables through a quadratic discriminant
> analysis.
> It seems to me that a robust criterion is the value of the discriminatory
> power
> (i.e. the ratio of the separation of the class means to within-class
> variance)
> How can I obtain this ratio from V & R's qda() output ?
> Thanks
> (I hope this question is relevant)
> -- 
> Daniel AMORESE
> Lab. M2C "Morphodynamique Continentale et Côtière"
> UMR CNRS 6143 Caen/Rouen
> Centre de Géomorphologie
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Thank you.
Your answer helps me a little (I regret help(qda) and "Modern Applied
Statistics
with S-plus" provide so sparse information about qda usage).
D. Amorese
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