Dual-energy X-ray absorptiometry (DXA) is a technique for measuring bonehealth. One of the most common measures is total body bone mineral con-tent (TBBMC). A highly skilled operator is required to take the measurements.Recently, a new DXA machine was purchased by a research lab and two oper-ators were trained to take the measurements. TBBMC for eight subjects wasmeasured by both operators. The units are grams (g). A comparison of themeans for the two operators provides a check on the training they received andallows us to determine if one of the operators is producing measurements thatare consistently higher than the other. Here are the data:Subject4Оperator51.328 1.335 1.079 | 1.227 | 0.936 1.006| 1.178 | 1.2871.323 1.322| 1.073 1.233 0.934 | 1.019 | 1.184 1.30412367812a) Are the two operator groups Independent or Dependent? Explain.b) Do we need to assume that both groups are Normally distributed? Explain.c) Use a significance test to examine the null hypothesis that the two op-erators have the same mean. Make your conclusion based on your teststatistics and critical value where a = .02.d) Use a 98% confidence interval to provide a range of differences that arecompatible with these data. What can you conclude? Is one of operatorssignificantly better than the other? Explain.e) The eight subjects used for this comparison were not a random sample.In fact, they were friends of the researchers whose ages and weights weresimilar to the types of people who would be measured with this DXA. Com-ment on the appropriateness of this procedure for selecting a sample, anddiscuss any consequences regarding the interpretation of the significancetesting and confidence interval results.

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Dual-energy X-ray absorptiometry (DXA) is a technique for measuring bone health. One of the most common measures is total body bone mineral con- tent (TBBMC). A highly skilled operator is required to take the measurements. Recently, a new DXA machine was purchased by a research lab and two oper- ators were trained to take the measurements. TBBMC for eight subjects was measured by both operators. The units are grams (g). A comparison of the means for the two operators provides a check on the training they received and allows us to determine if one of the operators is producing measurements that are consistently higher than the other. Here are the data: Subject 4 1.328 | 1.335 | 1.079 1.227 | 0.936 | 1.006 | 1.178 | 1.287 1.323 | 1.322 | 1.073 | 1.233 0.934 | 1.019 | 1.184 Operator 1 2 3 6 8 1 1.304

Dual-energy X-ray absorptiometry (DXA) is a technique for measuring bone health. One of the most common measures is total body bone mineral con- tent (TBBMC). A highly skilled operator is required to take the measurements. Recently, a new DXA machine was purchased by a research lab and two oper- ators were trained to take the measurements. TBBMC for eight subjects was measured by both operators. The units are grams (g). A comparison of the means for the two operators provides a check on the training they received and allows us to determine if one of the operators is producing measurements that are consistently higher than the other. Here are the data: Subject 4 1.328 | 1.335 | 1.079 1.227 | 0.936 | 1.006 | 1.178 | 1.287 1.323 | 1.322 | 1.073 | 1.233 0.934 | 1.019 | 1.184 Operator 1 2 3 6 8 1 1.304

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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