1. Explain the pros and cons of longitudinal, cross-sectional, and sequential designs.

2. Has the researcher made a type 1 or a type 2 error or arrived at the correct decision in each of the following examples? Why?

a. He rejects the null hypothesis even though in reality the independent variable has no effect. Type 1 error
b. He rejects the null hypothesis when it is in fact false. Type 1 error
c. He does not reject the null hypothesis although in reality the independent variable does have an effect. Type 2 error

3. Discuss one-way analysis of variance functions. How is between- and within-group variability used?

4. A researcher decides to test her hypothesis that some toys are more fun to play with than others, so she decides to compare fun toys or blocks with "un-fun" toys or stuffed animals. She is also interested in seeing whether a gender difference exists, so she adds gender as an independent variable.

a. What type of research design is required? Experimental Study Design

b. Diagram it.

c. If 20 subjects are required per cell, how many subjects are required overall for this study?