Concept/calculation questions:

1.Explain why the expected value for an F-Ratio is equal to 1 when there is no treatment effect.

2.Several factors influence the size of the F-ratio.For each of the following, indicate whether it would influence the numerator or the denominator of the F-ratio, and indicate whether the size of the F-ratio would increase or decrease.

Increase the difference between the sample means.

Increase the size of the sample variances.

3.Assuming that a researcher hopes to demonstrate that a treatment or group membership variable makes a significant difference in outcomes, which term does the research hope will be larger, MS_between or MS_within? Why?

4.What pattern in grouped data would make SS_within=0? What pattern within data would make SS_between = 0?(hint: try giving an example if you find explaining this one difficult).

5.A developmental psychologist is examining the development of language skills from age 2 to age 4. Three different groups of children are obtained, one for each age, with n = 16 children in each group. Each child is given a language-skills assessment test. The resulting data were analyzed with an ANOVA to test for mean differences between age groups. The results of the ANOVA are presented in the following table. (Hint: Start with df)

Fill in all missing values.

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