Observational Studies, Experiments, and Surveys

Topic Page

Questions

• A random sample of 40 tea drinkers scores much lower on a stress scale than a random sample of those who do not drink tea. Does drinking tea lower stress?
• You weigh 30 people who exercise every day, and you weigh 30 people who do not get regular exercise. The exercise group has a mean weight which is 22 pounds less than the non-exercise group's mean. Can you conclude that exercise causes people to weigh less?
• How do you minimize response bias?
• What is non response bias?
• What are some basic guidelines concerning the design of a questionnaire?
• What is wrong with the answer choices to the question: How much did you like your statistics course this semester? (A.) Not at all (B.) A lot (C.) It was awesome!
• What are some guidelines for creating appropriate questions for a questionnaire?
• How did you find the seminar?
• Suppose a survey of 511 women in the United States found that more than 63% are the primary investor in their household. Which part of the survey represents the descriptive branch of statistics?
• What is the difference between a casual relationship and correlation?
• What is the sample mean for the data?