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- A research center survey of 2,484 adults found that 1,942 had bought something online. Of these online shoppers, 1,295 are weekly online shoppers. Complete parts (a) through (c) below. a. Construct a 95% confidence interval estimate of the population proportion of adults who had bought something online. Sas (Round to four decimal places as needed.) led b. Construct a 95% confidence interval estimate of the population proportion of online shoppers who are weekly online shoppers. Sas (Round to four decimal places as needed.) c. How would the director of e-commerce sales for a company use the results of (a) and (b)? O A. Since a greater proportion of adults have purchased something online than are weekly online shoppers, the director of e-commerce sales may want to focus on those adults who have purchased something online. led O B. The information cannot be compared because it is derived from two different opinions. O C. Agreater proportion of adults have purchased something online, but…Assume that both populations are normally distributed. a) Test whether u >H2 at the a = 0.01 level of significance for the given sample data. b) Construct a 99% confidence interval about u - 42- Sample 1 28 52.6 Sample 2 23 44.1 9.4 O A. Ho: H1 H2 O B. Ho: H1 = H2, H:Hq H2, HHy H2 Determine the test statistic. t= (Round to two decimal places as needed.) Approximate the P-value. Choose the correct answer below. O A. P-value 20.10 O B. P-value <0.01 O C. 0.05 s P-value <0.10 O D. 0.01 SP-value <0.05 Should the hypothesis be rejected at the a = 0.01 level of significance? V the null hypothesis because the P-value is V the level of significance. b) The confidence interval is the range from to (Round to twwo decimal places as needed. Use ascending orderPain after surgery: In a random sample of 54 patients undergoing a standard surgical procedure, 15 required medication for postoperative pain. In a random sample of 94 patients undergoing a new procedure, only 16 required pain medication. Part: 0/ 2 Part 1 of 2 (a) Construct a 99% confidence interval for the difference in the proportions of patients needing pain medication between the old and new procedures. Let p, denote the proportion of patients who had the old procedure needing pain medication. OL Use tables to find the critical value and round the answer to at least three decimal places. A 99% confidence interval for the difference in the proportions of patients needing pain medication between the old and new procedures isA) State the hypothesis for this test B) construct a 95 % confidence interval about the sample mean of stocks traded in 2014 C) will the researcher reject the null hypothesisAssume that both populations are normally distributed. a) Test whether u > H2 at the a = 0.01 level of significance for the given sample data. b) Construct a 99% confidence interval about u - 42. 177 Sample 1 24 51.7 9.5 Sample 2 43.1 99 O A. Ho: H1 = H2, H:Hq>H2 O B. Ho: H1 = H2, HH1H2, H1: H1 H2 Determine the test statistic. %3D (Round to two decimal places as needed.) Approximate the P-value. Choose the correct answer below. O A. P-value 20.10 O B. P-value <0.01 O C. 0.01 s P-value <0.05 O D. 0.05 s P-value <0.10 Should the hypothesis be rejected at the a = 0.01 level of significance? V the null hypothesis because the P-value is the level of significance. b) The confidence interval is the range from to (Round to two decimal places as needed. Use ascending order.)A simple random sample of size n=40 is drawn from a population. The sample mean is found to be x=121.9 and the sample standard deviation is found to be s=12.8. Construct a 99% confidence interval for the population mean. a.) what is the lower bound? b.) what is the upper bound?Exercise 1: You are interested in determining the average number of social media accounts people have. You interview 30 people at random and the number of social media accounts they have has a sample mean of 7.1 and a sample standard deviation of 2.09. a) b) Define the parameter of interest. State and check if the assumptions needed for constructing the appropriate CI for the parameter of interest are satisfied. c) Find a 90% confidence interval for the parameter defined in part a). Use the table, not the calculator to find the appropriate critical value. d) Write a sentence to interpret the CI computed in part c).A professor at a local university wish to determine whether there is a significant difference in the average of final examination marks between the students who took his STA404 course online and face-to-face. Fifteen students were randomly selected from each group and the final examination marks were recorded. Hence, he analysed the data using IBM SPSS and the results are as follows. Independent Samples Test Levene's Test for Equality of F Variances Sig. t-test for Equality of Means t df Sig. (2-tailed) Mean Difference Std. Error Difference 95% Confidence Interval of the Difference b) Find the value of W. Lower Upper a) Are the variances of the two populations equal? Use α=0.05. Mark Equal variances assumed 2.041 .164 -1.524 W .139 -6.42000 4.21320 X Y Equal variances not assumed -1.524 24.625 .140 -6.42000 4.21320 -15.10390 2.26390Exercise 5: Confidence Intervals for Proportions Quinnipiac University Poll is a leading polling organization. In May 2019, it released a survey conducted from May 16 to May 20, 2019 of 1,078 self-identified registered voters. The poll asked a series of questions about a woman’s right to have a legal abortion. Here is question 47: How about when a pregnancy was caused by rape or incest; do you think abortion should be legal in this situation or not? Here are the percentage of respondents, broken out by political affiliation, who support the right of a woman to have an abortion under these conditions. Republican Democrat Independent Support 68% 92% 83% Sample Size, n 313 345 323 A)What are the point estimates? B)What is the appropriate z-value to use when constructing a confidence interval using a 95 confidence level? C)Calculate the three confidence intervals. Do this by hand and use Excel.
