21 % selected health care as the sector most likely to lead the market in the next 12 months. When asked to estimate how long it would take for technology and telecom stocks to resume sustainable growth , the managers ' average response was 25 years . a. Cite two descriptive statistics b. Make an inference about the population of all investment managers concerning the av - crage return expected on equities over the next 12 months c. Make an inference about the length of time it will take for technology and telecom stocks to resume sustainable growth 21 . A seven -year medical research study reported that women whose mothers took the drug DES during pregnancy were twice as likely to develop tissue abnormalities that might lead to cancer as were women whose mothers did not take the drug . a. This study involved the comparison of two populations . What were the populations ? b. Do you suppose the data were obtained in a survey or an experiment ? C. For the population of women whose mothers took the drug DES during pregnancy, a sample of 3980 women showed 63 developed tissue abnormalities that might lead to cancer . Provide a descriptive statistic that could be used to estimate the number of women out of 1000 in this population who have tissue abnormalities d. For the population of women whose mothers did not take the drug DIS during preg - nancy. what is the estimate of the number of women out of 1000 who would be ex- pected to have tissue abnormalities c. Medical studies often use a relatively large sample (in this case , 3980 ). Why ? 22. In the fall of 2003 , Amold Schwarzenegger challenged Governor Gray Davis for the gov - ernorship of California. A Policy Institute of California survey of registered voters reported Arnold Schwarzenegger in the lead with an estimated 54% of the vote (Newsweek , Sep - tember 8, 2003 ). a. What was the population for this survey ? b. What was the sample for this survey ? :. Why was a sample used in this situation ? Explain 23. Nielsen Media Research conducts weekly surveys of television viewing throughout the United States , publishing both rating and market share data . The Nielsen rating is the per - centage of households with televisions watching a program . while the Nielsen share is the percentage of households watching a program among those households with televisions in use . For example , Nielsen Media Research results for the 2003 Baseball World Series be- tween the New York Yankees and the Florida Marlins showed a rating of 12.8% and a share of 22 % (Associated Press , October 27, 2003 ). Thus , 12.8 % of households with televisions were watching the World Series and 22% of households with televisions in use were watch- ing the World Series. Based on the rating and share data for major television programs, Nielsen publishes a weekly ranking of television programs as well as a weekly ranking of the four major networks : ABC , CBS , NBC , and Fox . a. What is Nielsen Media Research attempting to measure ? b. What is the population ? C. Why would a sample be used in this situation ? d. What kinds of decisions or actions are based on the Nielsen rankings ? 24. A sample of midterm grades for five students showed the following results : 72 , 65. 82, 90, 76. Which of the following statements are correct , and which should be challenged as be- ing too generalized ? a. The average midterm grade for the sample of five students is 77. b. The average midterm grade for all students who took the exam is 77 C. An estimate of the average midterm grade for all students who took the exam is 77 . d. More than half of the students who take this exam will score between 70 and 85. e. If five other students are included in the sample , their grades will be between 65 and 90