HW1

1.1

• 1. Statistics is obtaining and using information or data to reduce uncertainty and to solve problems. Statistics can also provide a measure of confidence
• 3. individual
• 5. A statistic is a numerical summary of a sample. A parameter is a numerical summary of a population.
• 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: all teenagers ages 13-17 years old who live in the U.S. sample: 1028 teenagers ages 13-17 years old that live in the U.S.
• 40. population: all Coca-Cola bottles filled on October 15 sample: 50 Coca-Cola bottles filled on October 15
• 41. population: all soybean plants owned by the farmer sample: 100 soybean plants chosen at random by the farmer
• 42. population: all U.S. households sample: 50,000 U.S. households surveyed

1.2

• 13. observational
• 14. experiment
• 15. experiment
• 16. observational
• 17. 1. cohort study because a group of individuals (1739 people) are being studied over a long period of time (10 years)

2. Response variable: Whether an individual has heart disease or not Explanatory variable: Whether individual is happy or not
3. There could be possible lurking variables that are affecting the data and causing confounding to occur.

• 18. 1. cross-sectional study because this study collects information over a short period of time

2. Response var: whether skin cancer occurs in individual or not Explanatory var: whether individual consumes coffee or not
3. Lurking variables not accounted for in the study can affect the value of the response variable. Therefore, it is important to adjust for these variables because adjusting will yield more accurate results.