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An experimental bumper was designed to reduce damage in low-speed collisions. This bumper was installed on an experimental group of vans in a large fleet, just now not on a control group. At the condition of a trial period, accident data showed 12 emplacement incidents for the experimental group and 9 repair incidents for the control group. fomite downtime (in days per repair incident) is shown to a lower place. At ?= .05, did the new bumper reduce downtime? (a) escape ahead stacked dot plots of the data (a sketch is OK). (b) snuff it in the hypotheses. (c) State the decision ascertain and sketch it. (d) take on the establish statistic. (e) engender a decision. (f ) Find the p-value and interpret it. (g) Do you think the dissimilitude is large enough to be fundamental? Explain. (Data are from an unpublished study by Floyd G. Willoughby and Thomas W. Lauer, Oakland University.) radical bumper (12 repair incidents): 9, 2, 5, 12, 5, 4, 7, 5, 11, 3, 7, 1 comprise gro up (9 repair incidents): 7, 5, 7, 4, 18, 4, 8, 14, 13 Solution a) Dot plot of the data is devoted below [pic] [pic] b) The nonentity and alternative hypothesis are [pic] and [pic]. c) Assuming embody variance, at ? = 0.05, from Students t distribution with [pic] = 12 + 9 2 = 19 degrees of freedom, the critical value of the test is obtained as 1.729. Thus, the decision rule is Reject H0 if [pic] < 1.729. The sketch of the do away withion region is devoted below.

[pic] d) The test statistic is addicted by, [pic], where [pic]. From the precondition data, [pic] = 5.92, [pic]= 8.89, [pic] = 3.42, [pic] = 4.96. Therefore, [pic]= 17.148 Thus, [pic] = 1.63. e) Since t = 1.63 > 1.729, we ! disregard to reject the null hypothesis. f) The p-value of the test is given by, P[ t < -1.63] = 0.06 The decision rule using p-value is reject the null hypothesis Ho if p-value < 0.05. Since the p-value > 0.05, we fail to reject the null hypothesis. This is a close decision. g) A ingest difference of approximately 3 days downtime would be considered...If you necessitate to get a climb essay, order it on our website: OrderEssay.net

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