1. Were any causal assertions made or implied in the hypotheses or in subsequent discussion? What approach was used to demonstrate the existence of causal effects? Were all 3 issues in establishing causal relationships addressed (temporal order, correlation, removing rival causal factors)? What, if any, variables were controlled in the analysis to reduce the risk of spurious relationships and rival causal factors?
2. Which of the 8 possible variables (factors) listed on page 68 of your textbook that affect the internal validity of the conclusions concern you the most as it relates to this research article? Explain and justify your response.
3. Briefly describe the difference between a cross-sectional and longitudinal design. What are the pros and cons of using each? Describe the longitudinal aspect of Kempinen & Kurlychek’s (2003).
