The carbon monoxide diffusing capacity of the lung (DL) for a random sample of current smokers...

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The carbon monoxide diffusing capacity of the lung (DL) for a random sample of current smokers was as follows: 103.768 92.295 100.615 102.754 88.602 61.675 88.017 108.579 73.003 90.677 71.210 73.154 123.086 84.023 82.115 106.755 91.052 76.014 89.222 90.479 Can we conclude that the mean DL reading for current smokers differs from 100, which is the known mean DL reading for nonsmokers? If we use a = 0.01 as our level of significance, select all of the following choices that are true. 14 of the 20 data values are less than 100. Since 70% is way greater than 50%, we may conclude that DL readings for smokers are less than 100. We would get a different conclusion if we used .05 as our level of significance. The p-value is found by doubling tcdf(-1E99, -3.044, 19). We must assume the normal probability plot is roughly linear in order to perform the required test. When performing the test statistic approach, the critical values (to three decimal accuracy) are t = +2.576. We fail to reject the null hypothesis. To three decimal accuracy, the standard error of the mean is 3.333. We conclude that the mean DL reading for current smokers differs from that of nonsmokers. A one-tailed test is performed. When performing the classical approach, the lower critical value is 89.95, to two decimal accuracy. The carbon monoxide diffusing capacity of the lung (DL) for a random sample of current smokers was as follows: 103.768 92.295 100.615 102.754 88.602 61.675 88.017 108.579 73.003 90.677 71.210 73.154 123.086 84.023 82.115 106.755 91.052 76.014 89.222 90.479 Can we conclude that the mean DL reading for current smokers differs from 100, which is the known mean DL reading for nonsmokers? If we use a = 0.01 as our level of significance, select all of the following choices that are true. 14 of the 20 data values are less than 100. Since 70% is way greater than 50%, we may conclude that DL readings for smokers are less than 100. We would get a different conclusion if we used .05 as our level of significance. The p-value is found by doubling tcdf(-1E99, -3.044, 19). We must assume the normal probability plot is roughly linear in order to perform the required test. When performing the test statistic approach, the critical values (to three decimal accuracy) are t = +2.576. We fail to reject the null hypothesis. To three decimal accuracy, the standard error of the mean is 3.333. We conclude that the mean DL reading for current smokers differs from that of nonsmokers. A one-tailed test is performed. When performing the classical approach, the lower critical value is 89.95, to two decimal accuracy.