study was recently reported comparing the effects of different dietary patterns on blood pressure within an 8-week follow-up period [16]. Subjects were randomized to three groups: A, a control diet group, N = 154; B, a fruits-andvegetables diet group, N = 154; C, a combination-diet group consisting of a diet rich in fruits, vegetables, and lowfat dairy products and with reduced saturated and total fat, N = 151. The results reported for systolic blood pressure (SBP) are shown in Table 8.29.
Table 8.29 Effects of dietary pattern on change in SBP
Suppose we want to compute a two-sided p-value for this comparison. Without doing any further calculation, which statement(s) must be false?
(1) p = .01 (2) p = .04 (3) p = .07 (4) p = .20
(Note: The actual p-value may differ from all these values.)
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Fundamentals of Biostatistics
- A pathological video game user (PVGU) is a video game user that averages 31 or more hours a week of gameplay. According to the article “Pathological Video Game Use among Youths: A Two-Year Longitudinal Study” (Pediatrics, Vol. 127, No. 2, pp. 319–329) by D. Gentile et al., in 2011, about 9% of children in grades 3–8 were PVGUs. Suppose that, today, five youths in grades 3–8 are randomly selected. Let X represent the number of youths who are PVGUs. n = p = 1 – p = Prepare the probability distribution for the random variable X. Complete the following table. Round your answers to 4 decimal places e.g. 0.XXXX or .XXXX. X = x P(X=x) 0 1 2 3 4 5 ∑=1.0000∑=1.0000 Calculate the probability that EXACTLY three youths are PVGUs. Round your answers to 4 decimal places e.g. 0.XXXX or .XXXX. P(X = 3) = Calculate the probability that AT LEAST two youths are PVGUs. Round your answers to 4 decimal places e.g. 0.XXXX or .XXXX. P(X ≥ 2) = Calculate the…arrow_forwardA pathological video game user (PVGU) is a video game user that averages 31 or more hours a week of gameplay. According to the article “Pathological Video Game Use among Youths: A Two-Year Longitudinal Study” (Pediatrics, Vol. 127, No. 2, pp. 319–329) by D. Gentile et al., in 2011, about 9% of children in grades 3–8 were PVGUs. Suppose that, today, five youths in grades 3–8 are randomly selected. Let X represent the number of youths who are PVGUs. Calculate the probability that EXACTLY three youths are PVGUsarrow_forwardA study was undertaken to investigate the effectiveness of an aquarobic exercise program for patients with osteoarthritis. A convenience sample of 70 individuals with arthritis was selected, and each person was randomly assigned to one of two groups. The first group participated in a weekly aquarobic exercise program for 8 weeks; the second group served as a control. Several pieces of data were collected from the individuals, including their total cholesterol (mg). Determine if there is a significant difference in the mean cholesterol for the two groups (aquarobic & control) at the start of the study using a significance level of 0.01. Difference Sample Diff. Std. Error df Aquarobic - Control -13.9045 6.8214 67.8635 What hypotheses should be tested? Make sure to select the hypotheses which are written with notation consistent with the type of samples selected. Ho:μd=0Ho:μd=0Ha:μd>0Ha:μd>0 Ho:μd=0Ho:μd=0Ha:μd<0Ha:μd<0 Ho:μ1=μ2Ho:μ1=μ2Ha:μ1<μ2Ha:μ1<μ2…arrow_forward
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