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Fortified Juice and PTH. V. Tangpricha et al. did a study to determine whether fortifying orange juice with Vitamin D would result in changes in the blood levels of five biochemical variables. One of those variables was the concentration of parathyroid hormone (PTH), measured in picograms/milliliter (pg/mL). The researchers published their results in the paper “Fortification of Orange Juice with Vitamin D: A Novel Approach for Enhancing Vitamin D Nutritional Health” (American Journal of Clinical Nutrition, Vol. 77, pp. 1478–1483). Concentration levels were recorded at the beginning of the experiment and again at the end of 12 weeks. The following data, based on the results of the study, provide the decrease (negative values indicate increase) in PTH levels, in pg/mL, for those drinking the fortified juice and for those drinking the unfortified juice.
At the 5% significance level, do the data provide sufficient evidence to conclude that drinking fortified orange juice reduces PTH level more than drinking unfortified orange juice? (Note: The
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Introductory Statistics (10th Edition)
- The spotted lanternfly, Lycorma delicatula, is an invasive species to the United States that has the potential to do significant agricultural damage. An ecologist is studying the relationship between the size of the female spotted lanternflies and the number of eggs they produce. The data are summarized below. Length of insect: AVG = 1 inch, SD = 0.15 inchNumber of eggs: AVG = 40 eggs, SD = 5 eggsr = 0.2 Using regression, we can say that the average number of eggs produced by female spotted lanternflies who are 1.1 inch long is closest to... Group of answer choices 42 39 40 41arrow_forwardA medical student at a community college in city Q wants to study the factors affecting the systolic blood pressure of a person (Y). Generally, the systolic blood pressure depends on the BMI of a person (B) and the age of the person A. She wants to test whether or not the BMI has a significant effect on the systolic blood pressure, keeping the age of the person constant. For her study, she collects a random sample of 150 patients from the city and estimates the following regression function: Y= 15.50 +0.90B + 1.10A. (0.48) (0.35) The test statistic of the study the student wants to conduct (Ho: B, =0 vs. H4: B, #0), keeping other variables constant is. (Round your answer to two decimal places.) At the 5% significance level, the student will v the null hypothesis. Keeping BMI constant, she now wants test whether the age of a person (A) has no significant effect or a positive effect on the person's systolic blood pressure. So, the test statistic associated with the one-sided test the…arrow_forwardA study published by Babcock and Marks (2010) showed that the average full-time U.S. college student studied for μ = 14 hours per week (SD = 4.8 hours per week) in 2005. We want to know if this average has changed in the past 15 years. In other words, we are going to do a study in which we try to determine whether there has been an impact of the passage of time on the amount of time college students spend studying. We selected a sample of n = 64 of today’s college students and find that they spent an average of M = 12.5 hours per week studying. Does this sample indicate a significant change in the number of hours spent studying? Use a two-tailed test (this means non-directional hypothesis) with α = .05.arrow_forward
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- A horse is fed 19.1 pounds per day of hay (AF basis), and excretes 20.6 pounds per day of feces (as is) and 9.5 pounds per day of urine (wet). Lab analysis shows that the hay contains 91.2% DM and 59.1% neutral detergent fiber (NDF) on a DM basis, and the feces contains 30.4% DM and 52.9% NDF on a DM basis. What is the percent NDF digestibility of the hay? You Answered Correct Answer 67.82 margin of error 0.5arrow_forwardIs Your Nose Getting Bigger?Next time you see an elderly man, check out his nose and ears! While most parts of the human body stop growing as we reach adulthood, studies show that noses and ears continue to grow larger throughout our lifetime. In one study1 examining noses, researchers report "Age significantly influenced all analyzed measurements:" including volume, surface area, height, and width of noses. In a test to see whether males, on average, have bigger noses than females, the study indicates that "p<0.01."Let group 1 be males and group 2 be females.(a) State the hypotheses. Your answer should be an expression composed of symbols H0:_ vs Ha:_ (c) Interpret the conclusion in context. -We have evidence that males have bigger noses than females, on average. -We do not have evidence that males have bigger noses than females, on average. -We have evidence that males and females have the same size noses, on average. -We do not have evidence that males and females have the same…arrow_forwardIs Your Nose Getting Bigger?Next time you see an elderly man, check out his nose and ears! While most parts of the human body stop growing as we reach adulthood, studies show that noses and ears continue to grow larger throughout our lifetime. In one study1 examining noses, researchers report "Age significantly influenced all analyzed measurements:" including volume, surface area, height, and width of noses. In a test to see whether males, on average, have bigger noses than females, the study indicates that "p<0.01."Let group 1 be males and group 2 be females.1Sforza C, Grandi G, De Menezes M, Tartaglia GM, Ferrario VF, "Age- and sex-related changes in the normal human external nose", Forensic Science International, 2011 Jan 30;204(1-3):205.e1-9. (a) State the hypotheses. Your answer should be an expression composed of symbols: =,≠,<,>,μ,μ1,μ2,p,p1,p2,ρ,p^,p^1,p^2,r. H0: vs Ha:Editarrow_forward
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- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill