HW1

1.1

• 1. Statistics is a process. It is the science of collecting, organizing, summarizing and analyzing information to draw conclusions or answer questions. It can provide confidence in its conclusions, however, the solutions cannot provide 100% certainty. Statistics has many goals, one of which is to understand how and why things vary.
• 3. Individual.
• 5. 1. Statistic. 2. 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: Teenagers 13-17 years old in the USA. Sample: Teenagers 13-17 years old in the USA with the Gallup Organization.
• 40. Population: All Coca Cola bottles filled October 15. Sample: 50 bottles of Coca Cola selected by the manager.
• 41. Population: All the soybean crop owned by the farmer. Sample: The 100 selected plants.
• 42. Population: All households in the United States. Sample: The 50,000 households chosen for the report.

1.2

• 13. Observational.
• 14. Experiment.
• 15. Experiment.
• 16. Observational.

1. This is a cohort study because the patients were observed for a long period of time (10 years).

2. The response variable is whether or not the individuals had heart disease. The explanatory varibale is weather or not the individuals were happy.

3. There could be a confounding because of the lurking variables such as genetics or lifestyle. Some individuals might eat healthier than others, for example, affecting their chances of having heart disease.

1. This is a case-control study because it is retrospective. The researchers asked the women their habits after-the-fact. They are looking at existing habits.

2. The response variable is whether or not the women have nonmelanoma skin cancer. The explanatory variable is how much coffee the individuals consumed daily.

3. This is importance because the researchers must take into account confounding factors when, for instance lifestyle, age or other variables affect the results of the study. By adjusting for outside factors, the results better reflect the effects of the variable in question i.e. Coffee