1. If test scores and self-esteem are positively correlated, what are three possible directions of causality that might explain this correlation?
Ans: It is possible that high test scores increase self-esteem. It is also possible that people with high self-esteem score higher on exams. Lastly, it is possible that family income increases both the test scores and self-esteem.
Learning Objective: 15-2: What can you learn from testing relationships between measures?
Cognitive Domain: Application
Answer Location: Correlation Versus Causation
2. What does an R2 value close to 1 tell you about your linear regression equation?
Ans: An R2 value close to 1 tells that your regression equation fits the data very well.
Learning Objective: 15-4: What does it mean to find the best-fit line for a set of data?
Cognitive Domain: Comprehension
Answer Location: R2 Fit Statistic