200 STA Quiz 2 Solutions 1) A numerical characteristic of the sample is known as what? Solution: Statistic 2) When asking survey questions, you should satisfy which of the following? Solution: All other choices are correct (Remove unnecessary complexity, Questions asked in a neutral manner, Put questions in random order) 3) Suppose you are conducting a study and decide to send out 12,000 surveys. If 8500 surveys are completed and returned, what is your response rate? Solution: 71% 4) Which of the following types of error is expected when doing inferential statistics and will not cause bias in your sample? The margin of error when calculated covers only this type of error. Solution: Random sampling error 5) The values of a statistic should satisfy which of the following? Solution: No bias and small variability 6) To ensure a statistic is not biased, should what be done? Solution: Take a random sample 7) If you increase the sample size in a study, what effect does that have on your margin of error if all other quantities are held constant? Solution: Margin of error decreases 8) A simple random sample of 2500 Americans shows that 1800 feel the president is performing well. Calculate the percent of the sample that feel the president is performing well. Solution: 72% 9) A simple random sample of 2500 Americans shows that 1800 feel the president is performing well. Calculate the margin of error for this percent. Solution: 2% 10) Suppose the president approval rating is 40% with 3% as the margin of error. Which of the following is the correct confidence statement? Solution: We are 95% confident that the percentage of Americans who feel the president is performing well is between 37% and 43%.