[R] Variance Homogenity

[Jose Herrera Bazán]

Working with living models sometimes the response is reflected in the 
variability more than the middle parameters, i.e., the variability can 
reflected the system response, p.ej., in toxicology models the variability 
in the response means something about the selective pressure, buy how to 
evaluated this variability?. The ANOVA Test evaluated difference between the 
medians using the variance between groups and behind groups, but i can´t use 
ANOVA if the two suposes don´t exists, normalitiy and variance homogeniety, 
then how to evaluated the differences in variance?, Barttlet Test evaluated 
the homoscedascity using the square sum and not the variance as a response 
variable. How could I evaluated the difference in groups with differents 
variances?. I don´t want use Kruskall-Wallis Test because my variable is 
continue and numerical. Do someone know what do must do it?

José Herrera Bazán
Science Faculty
UNAM


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