(a)
To Locate: The confidence interval for
To identify: The confidence interval for
To interpret: The results.
(b)
To Locate: The confidence interval for
To identify: The confidence interval for
To interpret: The results.
(c)
To Locate: The confidence interval for
To identify: The confidence interval for
To interpret: The results.
(d)
To Locate: The confidence interval for
To identify: The confidence interval for
To interpret: The results.
(e)
To Locate: The confidence interval for
To identify: The confidence interval for
To interpret: The results.
(f)
To Locate: The confidence interval for
To identify: The confidence interval for
To interpret: The results.
(g)
To identify: The ranks of the hosing system means.
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Statistics, Books a la Carte Edition (13th Edition)
- In building an arena, steel bars with a mean ultimate tensile strength of 400Megapascal (MPa) with a variance of 81 MPa were delivered by the manufacturer. The projectengineer tested 50 steel bars and found out that the mean ultimate tensile strength is 390 MPa.The decision for the extension of the contract with the manufacturer depends on the engineer.Test the hypothesis whether or not there is no significant difference between the two meansusing a two-tailed test with a = 0.01.arrow_forwardA recent study indicates that simply giving college students a pedometer can result inincreased walking (Jackson & Howton, 2008). Students were given pedometers for a 12-week period, and asked to record the average number of steps per day during weeks 1, 6,and 12. The following data are similar to the results obtained in the study. Use a repeatedmeasures ANOVA with α=.05 to determine whether the mean number of steps changessignificantly from one week to another. (do all 4 steps of conducting a hypothesistest!!): If there is a significant different, calculate the percent of variance that is explainedby treatment differences (??2) and conduct both Tukey and Scheffe post hoc tests. Person Week 1 Week 6 Week 12 Person Totals A 6 8 10 P=24 N=18 B 4 5 6 P=15 G=72 C 5 5 5 P=15 D 1 2 3 P=6 E 0 1 2 P=3 F 2 3 4 P=9 M=3 M=4 M=5 T=18 T=24 T=30…arrow_forwardWeinstein, McDermott, and Roediger (2010) report that students who were given questions to be answered while studying new material had better scores when tested on the material compared to students who were simply given an opportunity to reread the material. In a similar study, an instructor in a large psychology class gave one group of students questions to be answered while studying for the final exam. The overall average for the exam was μ = 73.4, but the n = 16 students who answered questions had a mean of M = 78.3 with a standard deviation of s = 8.4. For this study, did answering questions while studying produce significantly higher exam scores? Use a one-tailed test with α = .01 and the Distributions tool to help. (Round your answers to three decimal places, when needed.) sMM = t-critical = t = The results indicate: Failure to reject the null hypothesis; answering questions while studying did not produce significantly higher exam scores…arrow_forward
- Weinstein, McDermott, and Roediger (2010) report that students who were given questions to be answered while studying new material had better scores when tested on the material compared to students who were simply given an opportunity to reread the material. In a similar study, an instructor in a large psychology class gave one group of students questions to be answered while studying for the final exam. The overall average for the exam was μ = 73.4, but the n = 16 students who answered questions had a mean of M = 78.3 with a standard deviation of s = 8.4. For this study, did answering questions while studying produce significantly higher exam scores? Use a one-tailed test with α = .01arrow_forwardFor a sample of 400 correctional officers at Lucasville State Prison, a researcher believes there is a relationship between “years on the job” and “willingness to help raise money for adult charities.” Using the following data, test the null hypothesis at the .01 level of significance that willingness to help raise donations does not differ by length of service as a correctional officer. In so doing, identify: (1) the research and null hypothesis, (2) the critical value needed to reject the null, (3) the decision that you made upon analyzing the data, and (4) the conclusion you have drawn based on the decision you have made.arrow_forwardIn building an arena, steel bars with a mean ultimate tensile strength of 400 Megapascal (MPa) with a variance of 81 MPa were delivered by the manufactured. The project engineer tested 50 steel bars and found out that the mean ultimate tensile strength is 390 MPa. The decision for the extension of the contract with the manufacturer depends on the engineer. Test the hypothesis whether there is no significant difference between the two means using a two-tailed with a=0.01arrow_forward
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- A scrap metal dealer claims that the mean of his cash sales is 'no more that R80', but an Internal Revenue Service agent believes the dealer is untruthful. The agent randomly selects a sample of 20 cash customers and find the mean purchase to be R91, with a variance of R441. What is the critical value?arrow_forwardIn building an arena , steel bars with a mean ultimate tensile strength of 400 Megapascal (MPa ) with a variance of 81 MPa were delivered by the manufacturer . The project engineer tested 50 steel bars and found out that the mean ultimate tensile strength is 390 MPa The decision for the extension of the contract with the manufacture depends on the engineer . Test the hypothesis whether or not there is no significant difference between the two means using a two-tailed test with a = 0.01 1. What are the appropriate hypotheses for the two tailed test ? 2. What is the test statistic to be used and the reasons for its selection ? 3. What is the critical value c? 4. What is the value of the test statistic or the computed value? 5. Formulate a conclusion about the given situationarrow_forwardNutritionResearchers compared protein intake among threegroups of postmenopausal women: (1) women eating astandard American diet (STD), (2) women eating a lactoovo-vegetarian diet (LAC), and (3) women eating a strictvegetarian diet (VEG). The mean ± 1 sd for protein intake(mg) is presented in Table 12.29. 12.5 Using the data in Table 12.29, perform a multiplecomparisons procedure to identify which specific underlyingmeans are different.arrow_forward
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