A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand...

 

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A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Tread wear can vary considerably depending on the type of car, and the group is trying to eliminate this effect by installing the two brands on the same random sample of 12 cars. In particular, each car has one tire of each brand on its front wheels, with half of the cars chosen at random to have Brand 1 on the left front wheel, and the rest to have Brand 2 there. After all of the cars are driven over the standard test course for 20,000 miles, the amount of tread wear (in inches) is recorded, as shown in Table 1. Difference Car Brand 1 Brand 2 (Brand 1 - Brand 2) 0.352 0.288 0.064 2. 0.318 0.378 -0.060 0.272 0.194 0.078 4. 0.376 0.336 0.040 0.321 0.314 0.007 6. 0.271 0.330 -0.059 0.325 0.266 0.059 0.316 0.312 0.004 0.252 0.223 0.029 10 0.243 0.260 -0.017 11 0.358 0.369 -0.011 12 0.338 0.277 0.061 Table 1 Based on these data, can the consumer group conclude, at the 0.05 level of significance, that the mean tread wears of the brands differ? Answer this question by performing a hynothesis test regarding , (which is u with a letter "d" subscript), the population mean difference in tread wear for the two brands of tires. Assume that this population of differences (Brand 1 minus Brand 2) is normally distributed. Perform a two-tailed test. Then fill in the table below. Carry your intermediate computations to at least three decimal places and round your answers as specified in the table, (If necessary, consult a list of formulas.-) vPHIBSm12uyLCtearlkCnhmG0buHbVF2nq1RdUu9bBtcRxSTVavorVXwo?1oBw7QYjlbavbSPXtx-YCjsh_7mMm O CONFIDENCE INTERVALS AND HYPOTHESIS TESTING Hypothesis test for the difference of population means: Paired... Emmanuel V 0.338 0.277 0.061 Table 1 Based on these data, can the consumer group conclude, at the 0.05 level of significance, that the mean tread wears of the brands differ? Answer this question by performing a hypothesis test regarding u, (which is u with a letter "d" subscript), the population mean difference in tread wear for the two brands of tires. Assume that this population of differences (Brand 1 minus Brand 2) is normally distributed. Perform a two-tailed test. Then fill in the table below. Carry your intermediate computations to at least three decimal places and round your answers as specified in the table. (If necessary, consult a list of formulas.) Aa The null hypothesis: H. S. The alternative hypothesis: H :0 ロ=ロ OSO The type of test statistic: (Choose one) O<O The value of the test statistic: (Round to at least three decimal places.) The two critical values at the 0.05 level of significance: (Round to at least three decimal places.) | and | At the 0.05 level, can the consumer group conclude that the mean tread wears of the brands differ? O Yes No Activate Windos Go to Settings to act Ws Check Explanation 2020 McGraw-Hill Education, All Rights Reserved Terms of Use | Privacy Accessibility 2:18 11/28 Type here to search P. A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Tread wear can vary considerably depending on the type of car, and the group is trying to eliminate this effect by installing the two brands on the same random sample of 12 cars. In particular, each car has one tire of each brand on its front wheels, with half of the cars chosen at random to have Brand 1 on the left front wheel, and the rest to have Brand 2 there. After all of the cars are driven over the standard test course for 20,000 miles, the amount of tread wear (in inches) is recorded, as shown in Table 1. Difference Car Brand 1 Brand 2 (Brand 1 - Brand 2) 0.352 0.288 0.064 2. 0.318 0.378 -0.060 0.272 0.194 0.078 4. 0.376 0.336 0.040 0.321 0.314 0.007 6. 0.271 0.330 -0.059 0.325 0.266 0.059 0.316 0.312 0.004 0.252 0.223 0.029 10 0.243 0.260 -0.017 11 0.358 0.369 -0.011 12 0.338 0.277 0.061 Table 1 Based on these data, can the consumer group conclude, at the 0.05 level of significance, that the mean tread wears of the brands differ? Answer this question by performing a hynothesis test regarding , (which is u with a letter "d" subscript), the population mean difference in tread wear for the two brands of tires. Assume that this population of differences (Brand 1 minus Brand 2) is normally distributed. Perform a two-tailed test. Then fill in the table below. Carry your intermediate computations to at least three decimal places and round your answers as specified in the table, (If necessary, consult a list of formulas.-) vPHIBSm12uyLCtearlkCnhmG0buHbVF2nq1RdUu9bBtcRxSTVavorVXwo?1oBw7QYjlbavbSPXtx-YCjsh_7mMm O CONFIDENCE INTERVALS AND HYPOTHESIS TESTING Hypothesis test for the difference of population means: Paired... Emmanuel V 0.338 0.277 0.061 Table 1 Based on these data, can the consumer group conclude, at the 0.05 level of significance, that the mean tread wears of the brands differ? Answer this question by performing a hypothesis test regarding u, (which is u with a letter "d" subscript), the population mean difference in tread wear for the two brands of tires. Assume that this population of differences (Brand 1 minus Brand 2) is normally distributed. Perform a two-tailed test. Then fill in the table below. Carry your intermediate computations to at least three decimal places and round your answers as specified in the table. (If necessary, consult a list of formulas.) Aa The null hypothesis: H. S. The alternative hypothesis: H :0 ロ=ロ OSO The type of test statistic: (Choose one) O<O The value of the test statistic: (Round to at least three decimal places.) The two critical values at the 0.05 level of significance: (Round to at least three decimal places.) | and | At the 0.05 level, can the consumer group conclude that the mean tread wears of the brands differ? O Yes No Activate Windos Go to Settings to act Ws Check Explanation 2020 McGraw-Hill Education, All Rights Reserved Terms of Use | Privacy Accessibility 2:18 11/28 Type here to search P.