CHAPTER 8 Cooperative Group Activities 439 9. Out-of-class activity Groups of three or four students should go to the library and collect a sample consisting of the ages of books (based on copyright dates). Plan and describe the sampling plan, execute the sampling procedure, and then use the results to test the claim that the mean age of books in the library is greater than 20 years. 10. In-class activity Each student should write an estimate of the age of the current president of the United States. All estimates should be collected, and the sample mean and standard deviation should be calculated. Then test the hypothesis that the mean of all such estimates is equal to the actual current age of the president. 11. In-class activity A class project should be designed to conduct a test in which each student is given a taste of Coke and a taste of Pepsi. The student is then asked to identify which sample is Coke. After all of the results are collected, test the claim that the success rate is better than the rate that would be expected with random guesses. 12. In-class activity Each student should estimate the length of the classroom. The values should be based on visual estimates, with no actual measurements being taken. After the estimates have been collected, measure the length of the room, then test the claim that the sample mean is equal to the actual length of the classroom. Is there a “collective wisdom,” whereby the class mean is approximately equal to the actual room length? 13. Out-of-class activity Using one wristwatch that is reasonably accurate, set the time to be exact. Visit www.time.gov to set the exact time. If you cannot set the time to the nearest second, record the error for the watch you are using. Now compare the time on this watch to the time on other watches that have not been set to the exact time. Record the errors with negative signs for watches that are ahead of the actual time and positive signs for those watches that are behind the actual time. Use the data to test the claim that the mean error of all wristwatches is equal to 0. Do we collectively run on time, or are we early or late? Also test the claim that the standard deviation of errors is less than 1 min. What are the practical implications of a standard deviation that is excessively large? 14. In-class activity In a group of three or four people, conduct an extrasensory perception (ESP) experiment by selecting one of the group members as the subject. Draw a circle on one small piece of paper and draw a square on another sheet of the same size. Repeat this experiment 20 times: Randomly select the circle or the square and place it in the subject’s hand behind his or her back so that it cannot be seen, then ask the subject to identify the shape (without seeing it); record whether the response is correct. Test the claim that the subject has ESP because the proportion of correct responses is significantly greater than 0.5. 15. In-class activity After dividing into groups of between 10 and 20 people, each group member should record the number of heartbeats in a minute. After calculating the sample mean and standard deviation, each group should proceed to test the claim that the mean is greater than 48 beats per minute, which is the author’s result. (When people exercise, they tend to have lower pulse rates, and the author runs 5 miles a few times each week. What a guy!) 16. Out-of-class activity In groups of three or four, collect data to determine whether subjects have a Facebook page, then combine the results and test the claim that more than 3>4 of students have a Facebook page. 17. Out-of-class activity Each student should find an article in a professional journal that includes a hypothesis test of the type discussed in this chapter. Write a brief report describing the hypothesis test and its role in the context of the article.
RkJQdWJsaXNoZXIy NjM5ODQ=