Question

In ANOVA, variability between groups reflects _________, whereas variability within groups reflects __________ .

1. 		total variance; error variance
   		error variance ; total variance
   		random error; a true effect (if one exists)
   		both a true effect (if one exists) and random error; only random error
   		just a true effect (if one exists); random error

1. Rejecting the null hypothesis with the overall or omnibus One-way Analysis of Variance indicates that the:

   		mean of one sample differs significantly from the mean of at least one other sample.
   		mean of one sample differs significantly from the means of all the other samples.
   		means of all the samples differ significantly from each other.
   		outcome was common.

Answer 1

Solution :

Part 1 :

In ANOVA, variability between groups reflects just a true effect (if one exists), whereas variability within groups reflects random error.

Part 2 :

Rejecting the null hypothesis with the overall or omnibus One-way Analysis of Variance indicates that the at least one population mean differs significantly from the other population means.

Note : In part (2) none of the given options are correct. When we test any hypothesis, we conclude about the population parameter but in each of the given options they are concluding about the sample means. Hence, none of the given options are correct. However if in the first option we replace sample with population then first option will be correct.