PSYC 355 Analysis of Variance

PSYC 355 Analysis of Variance Liberty

1. A researcher uses analysis of variance to test for mean differences among three treatments with a sample of n = 12 in each treatment. The F-ratio for this analysis would have what df values?
2. An ANOVA is used to evaluate the mean differences among three treatment conditions with a sample of n = 12 participants in each treatment. For this study, what is dfwithin treatments?
3. A researcher reports an F-ratio with df = 1, 24 for an independent-measures experiment. If all the treatments had the same number of participants, then how many individuals were in each treatment?
4. In an ANOVA, what is represented by the letter T?
5. The following table shows the results of an analysis of variance comparing three treatments. What is the value of η 2 , the percentage of variance accounted for, for these data?
6. An ANOVA is used to evaluate the mean differences among three treatment conditions with a sample of n = 12 participants in each treatment. For this study, what is dfbetween treatments?
7. In analysis of variance, what is measured by the MS values?
8. A researcher uses an independent-measures t test to evaluate the mean difference between two treatments and obtains t(12) = 4.00. If the researcher had used an ANOVA to evaluate the data, what F-ratio would be obtained?
9. On average, what value is expected for the F-ratio if the null hypothesis is true?
10. If an analysis of variance produces a value of F = 1.00, then all the samples have the same mean.
11. Posttests are only needed if H 0 is rejected in an ANOVA comparing more than two treatments.
12. Posttests such as Scheffé are not necessary for an analysis of variance comparing only two treatment conditions.
13. For an ANOVA, when the null hypothesis is true, the F-ratio is balanced so that the numerator and the denominator are both measuring the same sources of variance.
14. For an independent-measures ANOVA comparing four treatment conditions, dfbetween = 3.
15. A research report presents the results of an independent-measures ANOVA as follows: F (3, 28) = 5.36, p < .01. If all the samples were the same size, then each sample had n = 7 participants.