HW1

1.1

• 1. The logic of uncertainty.
• 3. Individual.
• 5. Statistic, parameter.
• 7. Parameter.
• 9. Statistic.
• 11. Parameter.
• 13. Statistic.
• 15. Qualitative.
• 17. Quantitative.
• 19. Quantitative.
• 21. Qualitative.
• 23. Discrete.
• 25. Continuous.
• 27. Continuous.
• 29. Discrete.
• 39. Population: 13-17 year-olds in U.S., sample: 1028.
• 40. Population: Coca Cola from Oct. 15, sample: 50
• 41. Population: soybeans from farm, sample: 100.
• 42. Population: households within the U.S., sample: 50,000.

1.2

• 13. Observational study.
• 14. Observational study.
• 15. Experimental study.
• 16. Observational study.

1. This is a case control study because it is retrospective.
2. Response variable: whether individual has a heart disease or not. Explanatory variable: if the individual is happy or not.
3. Genetics is a confounding variable in this scenario because researchers cannot separate the two explanatory variables.

1. This is a cohort study because it is prospective.
2. Response variable: the association between daily coffee consumption and skin cancer. Explanatory variable: daily coffee consumption and occurrence of skin cancer.
3. It was necessary to alter these variables to certify that no other external factors could cause the decrease in skin cancer.