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Due: by Monday December 10, 2012 @ 8 AM (no exceptions) Please submit your assignment via Blackboard. Material Covered: Chapters 8, 9 Instructions: For each question that you wish to receive credit for, please show all of your work and make sure that you answer each problem completely in your own words. Please type your solutions (or write them neatly on separate paper and scan them to create a pdf or comparable file). You may use StatCrunch (statcrunch.american. edu Password: eagle The extra credit earned will go towards your Exam grades. A complete and correct answer for each part will earn you the number of points indicated next to the question. You may submit responses to one, two, three or all parts. 1. (1 point) From our text: p. 508: 8.92 In a random sample of 975 students from a large public university , it was found that 463 of the students changed majors during their college years. (a) Give a 95% confidence interval for the proportion of students at this university who changed majors (b) Express your results from (a) in terms of the percent of students who change majors (c) University officals concerned with counseling students are interested in the number of students who change majors rather than the proportion. The university has 37,500 undergraduate students. Convert the confidence interval you found in (a) to a confidence interval for the number of students who change majors during their college years 2. ( 1 point) From our text: p. 508: 8.93 Go the gallup poll web site gallup.com and final a poll that has several questions of intrest to you. Summarize the results of the poll giving margins of error and comparisons of interest(for this exercise you may assume that the data comes from an SRS) 3. (2 points) Please review “20 Questions A Journalist Should Ask About Poll Results” presented by NCPP (the National Council on Public Polls). For the poll that you selected for #2 please address at least five of the given questions. 4. (2 points) “In a study of eating disorders in female adolescents, Gross (1985) asked each of her participants whether they would prefer to gain weight, lose weight, or maintain their current weight. (Note: Only 12% of the girls in Gross’s sample were actually more than 15% above what normative tables say they should weigh, a common cutoff for a label of “overweight.”) When she broke down the data for girls by race (African-American versus white), she obtained the following results. (Other races have been omitted because of the small sample sizes.) Reducers Maintainers Gainers Total White 352 152 31 535 African-American 47 28 24 99 Total 399 180 55 634 From Fundamental Statistics for the Behavioral Sciences, 6th ed by David C. Howell a) Calculate the appropriate conditional distributions. b) State an appropriate set of hypotheses, and find the value of the χ2 statistic here and its P-value. c) What conclusions can you make based on your work from a and b?