Answers:1) Fobt= 7.54, reject Ho;, do Wilcoxon; Tobt= 90.5, reject Ho2) Fobt= 10.08, reject H0, do Wilcoxon; Zobt= 1.197, do not reject Ho 2.The same experiment was now repeated with a sample of 25 subjects. Again, group 1 did the testwith no time limit and group 2 was timed, yielding the following data:Group 1Group 272848164855876835692817260648855n₁ = 12n₂ = 13X-bar1= 79.5Si= 4.123X-bar₂ = 71.85$2= 13.088Did subjects in group 2 score lower, on average, than subjects in group 1? (a<.01)767983837281808380 1Sixteen subjects were randomly assigned to one of two groups in an experiment investigating theeffect of stress on test-taking performance. Subjects in group 1 completed a 100-item test with notime limit, while subjects in group 2 were allowed only 30 seconds to complete each item on thesame test. The following data were obtained:Group 1Group 2867272577865[I74728386724881547441X-bar₁ = 77.5X-bar₂ = 61.875$1 = 5.35$2 = 14.69Is there any significant difference between the performance of the two groups? (a <.05)

Given that Xbar1 = 77.5 with s1 = 5.35 and Xbar2 = 61.875 with s2 = 14.69Since you have posted more…

1 Sixteen subjects were randomly assigned to one of two groups in an experiment investigating the effect of stress on test-taking performance. Subjects in group 1 completed a 100-item test with no time limit, while subjects in group 2 were allowed only 30 seconds to complete each item on the same test. The following data were obtained: Group 1 Group 2 86 72 72 57 78 65 74 [I 72 83 86 72 48 81 54 74 41 X-bar₁ = 77.5X-bar₂ = 61.875 S₁ = 5.35 S2 = 14.69 Is there any significant difference between the performance of the two groups? (a <.05)

1 Sixteen subjects were randomly assigned to one of two groups in an experiment investigating the effect of stress on test-taking performance. Subjects in group 1 completed a 100-item test with no time limit, while subjects in group 2 were allowed only 30 seconds to complete each item on the same test. The following data were obtained: Group 1 Group 2 86 72 72 57 78 65 74 [I 72 83 86 72 48 81 54 74 41 X-bar₁ = 77.5X-bar₂ = 61.875 S₁ = 5.35 S2 = 14.69 Is there any significant difference between the performance of the two groups? (a <.05)

Holt Mcdougal Larson Pre-algebra: Student Edition 2012

1st Edition

ISBN:9780547587776

Author:HOLT MCDOUGAL

Publisher:HOLT MCDOUGAL

Chapter11: Data Analysis And Probability

Section: Chapter Questions

Problem 8CR

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