Worksheet
Assignment 6 (Two Way ANOVA) Worksheet
· Round each decimal answer to two digits or you will get incorrect results on your work. Only the precise answer obtained after rounding to the two decimal places will be correct.
Use the following information to complete the values for a Source table for a Two-Way (2 X 2) Independent Samples ANOVA and indicate if there are significant main effects or a significant interaction effect. The study was a test of maternal rat exposure to alcohol diet on offspring learning of 20 different aged rats. There were two levels of maternal diet (1 with alcohol and 1 without) and two age levels (adolescent versus mature rats). What are the following values in this study?
1. _________k for the maternal diet condition for this study.
2. _________ k for the age condition of the rat off spring.
3. _________ SStot
4. _________ dfa (maternal diet)
5. _________ dfb (age of rat)
6. _________ dfaxb (interaction of diet & age)
7. _________ dfwn
8. _________ dftot
9. _________ MS a (maternal diet)
10. _________ MS b (age of rat)
11. _________ MS axb
12. _________ MS wn
13. _________ Fa
14. _________ Fb
15. _________ Faxb
SS
df
MS
F
Maternal Diet
192.2
___________4.
___________9.
___________13.
Offspring Age
57.8
___________5.
___________10.
___________14.
Interaction of Diet & Age
168.2
___________6.
___________11.
___________15.
Within
(Error)
75.6
___________7.
___________12.
Total
___________3.
___________8.
16. What is the critical value, at the .05 significance level, for F from the F-table for the treatments and interaction effects with this effect df (numerator) and dfwn (denominator)? [Hint the df for the numerator in a 2 x 2 ANOVA will be the same for each treatment and for the interaction.
_______________
17. Based on your computed value of F and the critical value from the F-Table reported in #16,
was there a significant interaction effect in this study?
A. Yes
B. No