1. A statistically significant correlation has been found between alcohol consumption and birth rate in the US for the years 1947-1962. Describe the three different relationships/mechanisms (i.e. three possible relationships between the factors) that may explain this finding.

2. Givetwo reasonswhy researchers only can disconfirm but cannot"prove"their hypotheses.

3. What are demand characteristics? What is experimenter bias? Describe one methodological procedure for minimizing demand characteristics and one methodological procedure for reducing experimenter bias when conducting an experiment.

4. State 2 advantages and 2 disadvantages of using open-ended response formats in designing interviews and questionnaires. State 2 advantages and 2 disadvantages of using close-ended response formats. (8 points)

5. Name and define four threats to internal validity (4 points)AND explain how these problems are resolved by conducting a true experiment