18.22 please COMPARING TWO MEANS124 126 116 127 119 97 102 110 120 103 115111 107 100 107 115 111 97 112 104 106 113109 113 128 128 118 113 124 127 136 106 123466CHAPTER EIGHTEEN(a) Treat these data as SRSS from the population of adultlong-tailed finches in the wild. Make dotplots of both datasets and determine whether the use of a two-sample tprocedure is appropriate.test scores of 31 seventh-grade girls in a midwestern schdistrict:19114 100 104 89 102 91 114 114 103 10572(b) How much longer, on average, are the central tailfeathers of male long-tailed finches than those of thefemales? Give a 95% confidence interval for the differencein population mean length between the male and thefemale adult long-tailed finches.108 130 120 132 111 128 118 119 86111 103 74 112 107 103 98 96 112 112 0.The IQ test scores of 47 seventh-grade boys in the same18.22 Food counseling for obese children.According to the Centers for Disease Control andPrevention (CDC), obesity rates among U.S. childrenhave increased dramatically over the past three decades,from a low of about 5% to 18% as of 2010. A studyexamined the effect of family-based food-counselingsessions provided by trained professionals. The studyrandomly assigned obese children aged 9 to 12 years toeither the counseling intervention or a control group notreceiving any food counseling. The children's weightchanges (in pounds, lb) after 15 weeks are displayed inTable 18.3 for both conditions. 18district are as follows:93 123 79 119 110 110 107 105 105 110 7790 114 106(a) Plot both data sets using dotplots or histograms.Because the sample sizes are quite large, the t procedureswill work well even in the presence of skew or mildoutliers.(a) Make dotplots or histograms of both sets of data.Because the distributions are reasonably symmetricwith no extreme outliers, the t procedures will workwell.(b) Is there good evidence that obese children receivingfood counseling gain less weight over a 15-week period?State the hypotheses, carry out the corresponding test, andconclude in context.(b) Treat these data as SRSS from all seventh-gradestudents in the district. Is there good evidence that girlsand boys differ in their mean IQ scores? TABLE 18.3 Weight change (Ib) of obese children, by groupIntervention-16.7-14.8-11.9-9.7-9.6-8.8-8.0-7.1-6.6-6.0-5.6-5.6-5.5-5.5-5.1-5.0-5.0-4.8-4.4-4.4-4.1-4.0-4.0-3.6-3.5-3.2 -2.8-2.0-1.8-1.8-1.4-1.2-0.2-0.10.00.20.61.01.21.21.41.82.02.22.52.83.34.25.45.86.06.48.4Control12.010.09.08.67.16.76.14.84.64.52.82.82.82.71.81.6 1.00.70.40.10.1-5.1-5.1

Question

18.22 please COMPARING TWO MEANS124 126 116 127 119 97 102 110 120 103 115111 107 100 107 115 111 97 112 104 106 113109 113 128 128 118 113 124 127 136 106 123466CHAPTER EIGHTEEN(a) Treat these data as SRSS from the population of adultlong-tailed finches in the wild. Make dotplots of both datasets and determine whether the use of a two-sample tprocedure is appropriate.test scores of 31 seventh-grade girls in a midwestern schdistrict:19114 100 104 89 102 91 114 114 103 10572(b) How much longer, on average, are the central tailfeathers of male long-tailed finches than those of thefemales? Give a 95% confidence interval for the differencein population mean length between the male and thefemale adult long-tailed finches.108 130 120 132 111 128 118 119 86111 103 74 112 107 103 98 96 112 112 0.The IQ test scores of 47 seventh-grade boys in the same18.22 Food counseling for obese children.According to the Centers for Disease Control andPrevention (CDC), obesity rates among U.S. childrenhave increased dramatically over the past three decades,from a low of about 5% to 18% as of 2010. A studyexamined the effect of family-based food-counselingsessions provided by trained professionals. The studyrandomly assigned obese children aged 9 to 12 years toeither the counseling intervention or a control group notreceiving any food counseling. The children's weightchanges (in pounds, lb) after 15 weeks are displayed inTable 18.3 for both conditions. 18district are as follows:93 123 79 119 110 110 107 105 105 110 7790 114 106(a) Plot both data sets using dotplots or histograms.Because the sample sizes are quite large, the t procedureswill work well even in the presence of skew or mildoutliers.(a) Make dotplots or histograms of both sets of data.Because the distributions are reasonably symmetricwith no extreme outliers, the t procedures will workwell.(b) Is there good evidence that obese children receivingfood counseling gain less weight over a 15-week period?State the hypotheses, carry out the corresponding test, andconclude in context.(b) Treat these data as SRSS from all seventh-gradestudents in the district. Is there good evidence that girlsand boys differ in their mean IQ scores?> TABLE 18.3 Weight change (Ib) of obese children, by groupIntervention-16.7-14.8-11.9-9.7-9.6-8.8-8.0-7.1-6.6-6.0-5.6-5.6-5.5-5.5-5.1-5.0-5.0-4.8-4.4-4.4-4.1-4.0-4.0-3.6-3.5-3.2 -2.8-2.0-1.8-1.8-1.4-1.2-0.2-0.10.00.20.61.01.21.21.41.82.02.22.52.83.34.25.45.86.06.48.4Control12.010.09.08.67.16.76.14.84.64.52.82.82.82.71.81.6 1.00.70.40.10.1-5.1-5.1

Accepted Answer

A t-test analyzes whether the average of two groups statistically varied from one another. For…