A nine-laboratory cooperative study was performed to evaluate quality control for susceptibility tests with 30-μg netilmicin disks [6]. Each laboratory tested three standard control strains on a different lot of Mueller-Hinton agar, with 150 tests performed per laboratory. For protocol control, each laboratory also performed 15 additional tests on each of the control strains using the same lot of Mueller-Hinton agar across laboratories. The
Answer Problem 6.18 assuming each laboratory uses a common medium to perform the susceptibility tests.
Provide a point and
Table 6.11 Mean zone diameters with 30-μg netilmicin disks tested in nine separate laboratories
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- Patients suffering from rheumatic diseases or osteoporosis often suffer critical losses in bone mineral density (BMD). Alendronate is one medication prescribed to build or prevent further loss of BMD. Holcomb and Rothenberg (A-3) looked at 96 women taking alendronate to determine if a difference existed in the mean percent change in BMD among five different primary diagnosis classifications. Group 1 patients were diagnosed with rheumatoid arthritis (RA). Group 2 patients were a mixed collection of patients with diseases including lupus, Wegener’s granulomatosis and polyarteritis, and other vasculitic diseases (LUPUS). Group 3 patients had polymyalgia rheumatica or temporal arthritis (PMRTA). Group 4 patients had osteoarthritis (OA) and group 5 patients had osteoporosis (O) with no other rheumatic diseases identified in the medical record. Changes in BMD are shown in the following table. Discuss the Alendronate medication data in terms of variability. To determine if a difference…arrow_forwardFive samples of a ferrous-type substance were used to determine if there is a difference between a laboratory chemical analysis and an X-ray fluorescence analysis of the iron content. Each sample was split into two subsamples and the two types of analysis were applied, with the accompanying results. Assuming that the populations are normal, test at the 0.10 level of significance whether the two methods of analysis give, on the average, the same result.arrow_forwardTwo subspecies of dark-eyed juncos were studied by D. Cristol et al. One of the sub- species migrates each year, and the other does not. Several characteristics of 14 birds of each subspecies were measured, one of which was wing length. The following data, based on the results of the researchers, provide the wing lengths, in millimeters, for the samples of two subspecies. Assume that wing lengths in populations of subspecies are normally distributed.Migratory: n = 14, x ̄ = 82.1, s = 1.5 111Non-migratory: n = 14, x ̄ = 84.92, s = 1.69 222Conduct a hypothesis test to determine if the average wing lengths in two populations of subspecies are significantly different.(i.) State the hypotheses.(ii.) Test for equality of unknown population variances. (iii.) Calculate test statistic.(iv.) Calculate degrees of freedom.(v.) Calculate the p−value of the test.(vi.) State your decision based on the p−value.(vii.) Write the interpretationarrow_forward
- The drug BGH (Bovine Growth Hormone) is reported to increase the milk production in dairy cows. It is known that the average milk production of dairy cows not using BGH is 58 pounds per day. The drug was tested on nine randomly selected dairy cows and the following weights were recorded: 59, 48, 66, 65, 80, 73, 69, 62, 70. a. Construct a 95% CI for the mean weight of milk produced by cows using BGH. b. Interpret this CI, what can you say about the effect of BGH on production?arrow_forwardFive samples of a ferrous-type substance were used to determine if there is a difference between a laboratory chemical analysis and an X-ray fluorescence analysis of the iron content. Each sample was split into two subsamples and the two types of analysis were applied, with the accompanying results. Assuming that the populations are normal, test at the 0.02 level of significance whether the two methods of analysis give, on the average, the same resultarrow_forwardBlood cocaine concentration (mg/L) was determinedboth for a sample of individuals who had died fromcocaine-induced excited delirium (ED) and for a sampleof those who had died from a cocaine overdose withoutexcited delirium; survival time for people in bothgroups was at most 6 hours. The accompanying datawas read from a comparative boxplot in the article“Fatal Excited Delirium Following Cocaine Use” (J.of Forensic Sciences, 1997: 25–31). ED 0 0 0 0 .1 .1 .1 .1 .2 .2 .3 .3.3 .4 .5 .7 .8 1.0 1.5 2.7 2.83.5 4.0 8.9 9.2 11.7 21.0Non-ED 0 0 0 0 0 .1 .1 .1 .1 .2 .2 .2.3 .3 .3 .4 .5 .5 .6 .8 .9 1.01.2 1.4 1.5 1.7 2.0 3.2 3.5 4.14.3 4.8 5.0 5.6 5.9 6.0 6.4 7.98.3 8.7 9.1 9.6 9.9 11.0 11.512.2 12.7 14.0 16.6 17.8 a. Determine the medians, fourths, and fourth spreadsfor the two samples.b. Are there any outliers in either sample? Any extremeoutliers?c. Construct a comparative boxplot, and use it as abasis for comparing and contrasting the ED andnon-ED samples.arrow_forward
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- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill