Hello, I know how to test 2 variances, but how should I go about testing 4?
Here's the whole problem:
You want to see the effect of drugs on the reaction time. 4 independent samples of 7 people has been tested, one with no drug and the three others with a different drug each.
No drug: (mean sample) x_1=47.29 (variation of sample) S_1=9.24
Opium: x_2=52.14 S_2 = 7.14
Amphetamin: x_3=80.57 S_3=30.95
Morphine: x_4=82 S_4=8
a) Test the egality of the variances with a bilateral test, with alpha = 5%
b) Test the egality of the means with a variance analysis. Use alpha = 5%
I did b) with ANOVA but I have no clue how to do a)
Thanks