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Consider the population that consists of all employees of a large computer manufacturer. a. Give an example of a question about this population that could be answered by collecting data and using it to estimate a population characteristic. b. Give an example of a question about this population that could be answered by collecting data and using it to test a claim about this population.

Suppose that a study is carried out in which each student in a random sample selected from students at a particular college is asked whether or not he or she would purchase a recycled paper product even if it cost more than the same product that was not made with recycled paper. Would you use the resulting data to estimate a population mean or to estimate a population proportion? How did you decide?

Refer to the instructions prior to this exercise. A study of fast-food intake is described in the paper "What People Buy From Fast-Food Restaurants" (Obesity [2009]: 1369-1374). Adult customers at three hamburger chains (McDonald's, Burger King, and Wendy's) at lunchtime in New York City were approached as they entered the restaurant and were asked to provide their receipt when exiting. The receipts were then used to determine what was purchased and the number of calories consumed. The sample mean number of calories consumed was \(857,\) and the sample standard deviation was 677 . This information was used to learn about the mean number of calories consumed in a New York fast-food lunch.

Are people willing to eat blemished produce? An article that described the result of a survey of 2025 adult Americans was titled "Eight in Ten Americans Say Appearance Is at Least Somewhat Important When Shopping for Fresh Produce" (www .theharrispoll.com/business/Appearance-is-Important-When -Shopping-for-Produce.html, September \(22,2016,\) retrieved July 24,2017) . Is the inference described in the title of this article one that resulted from estimation or one that resulted from hypothesis testing? Explain.

Data from a poll of working women conducted in 2016 by Gallup led to the following estimates: Approximately \(48 \%\) of working women are actively looking for a different job and \(60 \%\) of working women rate greater work- life balance and well-being as a very important attribute in a new job ("Women in America: Work and a Life-Well Lived," www .gallup.com, retrieved November 8,2016 ). a. What additional information about the survey would you need in order to decide if it is reasonable to generalize these estimates to the population of all American adult working women? b. Assuming that the given estimates were based on a representative sample, do you think that the estimates would more likely be closer to the actual population values if the sample size had been 1000 or if the sample size had been 2000 ? Explain.

In a study of whether taking a garlic supplement reduces the risk of getting a cold, 146 participants were randomly assigned to either a garlic supplement group or to a group that did not take a garlic supplement ("Garlic for the Common Cold," Cochrane Database of Systematic Reviews, 2009). Based on the study, it was concluded that the proportion of people taking a garlic supplement who get a cold is lower than the proportion of those not taking a garlic supplement who get a cold. a. What claim about the effect of taking garlic is supported by the data from this study? b. Is it possible that the conclusion that the proportion of people taking garlic who get a cold is lower than the proportion for those not taking garlic is incorrect? Explain. c. If the number of people participating in the study had been \(50,\) do you think that the chance of an incorrect conclusion would be greater than, about the same as, or lower than for the study described?

Suppose that a study was carried out in which each student in a random sample of students at a particular college was asked if he or she was registered to vote. Would these data be used to estimate a population mean or to estimate a population proportion? How did you decide?