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The paper “Less Air Pollution Leads to Rapid Reduction of Airway Inflammation and Improved Airway
The authors of the paper used paired t tests to determine that there was a significant difference in the urban and rural means for each of these three measures. One of these tests resulted in a P-value less than 0.001, one resulted in a P-value between 0.001 and 0.01, and one resulted in a P-value between 0.01 and 0.05.
- a. Which measure (Eosinophils, FENO, or PEF) do you think resulted in a test with the P-value that was less than 0.001? Explain your reasoning.
- b. Which measure (Eosinophils, FENO, or PEF) do you think resulted in the test with the largest P-value? Explain your reasoning.
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Introduction to Statistics and Data Analysis
- The 5-year incidence of cardiovascular disease (CVD) in relation to smoking status was determined in a population sample of 1000 men, 18 years and older. At baseline, 30% of the men were classified as being current smokers and 70% as being non-smokers. At the end of the follow-up, 60 CVD events had occurred among the smokers and 70 events among the non-smokers. Construct a 2 x 2 table based on the data providedarrow_forwardplease help me solve sub-part darrow_forwardAn article in Plant Disease, "Effect of Nitrogen and Potassium Fertilizer Rates on Severity of Xanthomonas Blight of Syngonium Podophyllum" (1989, Vol. 73, No. 12, pp. 972-975) showed the effect of the variable nitrogen and potassium rates on the growth of "White Butterfly" and the mean percentage of disease. Data representative of that collected in this experiment is provided in the following table. Potassium (mg/pot/wk) Nitrogen (mg/pot/wk) 30 90 120 50 60.8 60.8 45.5 43.0 60.0 58.4 150 54.4 56.1 53.8 51.6 34.5 35.5 250 42.9 40.0 36.1 37.9 33.0 33.3 (a) Use the analysis of variance to test the appropriate hypotheses with a = 0.05. The effect of the variable nitrogen significant, the effect of the potassium rates significant, the interaction between the variable nitrogen and potassium rates significant. (b) Graphically analyze the residuals from this experiment. The residuals acceptable. (c) Estimate the appropriate variance component. Round your answers to 2 decimal places. Source…arrow_forward
- The data in the attached image represents blood pressure based on a new trial medication used in an experiment involving a total of 50 male and female subjects. There were two levels of treatment: 0 = placebo and 1 = treatment group. Family History Blood Pressure = Fam-Hist-BP; from the paternal side = PS; from the maternal side = MS; from both sides = BS; none on both sides or not known = N.; Blood pressure before the experiment = BP-Before-Exp; Blood pressure after the experiment = BP-After-Exp. Task: Construct a side-by-side boxplot to compare the variables BP-Before-Exp and BP-After-Exp.arrow_forwardThe data in the attached image represents blood pressure based on a new trial medication used in an experiment involving a total of 50 male and female subjects. There were two levels of treatment: 0 = placebo and 1 = treatment group. Family History Blood Pressure = Fam-Hist-BP; from the paternal side = PS; from the maternal side = MS; from both sides = BS; none on both sides or not known = N.; Blood pressure before the experiment = BP-Before-Exp; Blood pressure after the experiment = BP-After-Exp. Task: Construct a histogram to represent the family BP history, the subjects' BP before treatment and the subjects' BP after treatment.arrow_forwardThe data in the attached image represents blood pressure based on a new trial medication used in an experiment involving a total of 50 male and female subjects. There were two levels of treatment: 0 = placebo and 1 = treatment group. Family History Blood Pressure = Fam-Hist-BP; from the paternal side = PS; from the maternal side = MS; from both sides = BS; none on both sides or not known = N.; Blood pressure before the experiment = BP-Before-Exp; Blood pressure after the experiment = BP-After-Exp. Task: Find the mean and standard deviation for the family history group, the before treatment group, and the after treatment group.arrow_forward
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