7.4. Relieving pain with opioids. The Journal of the American Medical Association (March 6, 2018) published a study that compared opioid and non-opioid medications for the control of pain. A sample of 240 patients, all of whom were experiencing chronic back, hip, or knee pain, participated in the study. The patients were randomly divided into two groups. One group was prescribed opioids for pain management, while the other group was prescribed a non-opioid pain management therapy (e.g., acetaminophen, an over-the-counter drug). After 12 months of treatment, the level of pain of each patient was determined using the Brief Pain Inventory (BPI) scale, where scores range from 0 (no pain) to 10 (severe pain). One objective was to compare the mean pain levels of the two groups after 12 months of treatment. a. Is this an observational study or a designed experiment? Explain. b. Propose a regression model that will allow the researchers to compare the mean

7.4. Relieving pain with opioids. The Journal of the American Medical Association (March 6, 2018) published a study that compared opioid and non-opioid medications for the control of pain. A sample of 240 patients, all of whom were experiencing chronic back, hip, or knee pain, participated in the study. The patients were randomly divided into two groups. One group was prescribed opioids for pain management, while the other group was prescribed a non-opioid pain management therapy (e.g., acetaminophen, an over-the-counter drug). After 12 months of treatment, the level of pain of each patient was determined using the Brief Pain Inventory (BPI) scale, where scores range from 0 (no pain) to 10 (severe pain). One objective was to compare the mean pain levels of the two groups after 12 months of treatment. a. Is this an observational study or a designed experiment? Explain. b. Propose a regression model that will allow the researchers to compare the mean

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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A consumer advocacy group wanted to study whether different airline carriers differed in terms of their delayed flights. In particular, the researchers were interested in the relationship between p1, the proportion of Alpha Airlines flights that were delayed at least 15 minutes, and p2, the proportion of Beta Airlines flights that were delayed at least 15 minutes. A random sample of 1,000 Alpha flights and a separate random sample of 1,000 Beta flights found that 67 of the Alpha fights and 160 of the Beta flights were delayed at least 15 minutes. The conditions for inference were checked and verified. Does this set of samples provide strong evidence that Alpha Airlines has a smaller proportion of flights that are delayed at least 15 minutes than Beta Airlines, at the α = 0.05 significance level? Find the z-table here. A. The test statistic is z = –6.56 and the P-value ≈ 0. Since the P-value ≈ 0 < 0.05, there is not sufficient evidence that Alpha Airlines has fewer delayed…
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Does posting calorie content for menu items affectpeople’s choices in fast-food restaurants? According to results obtained by Elbel, Gyamfi, and Kersh(2011), the answer is no. The researchers monitoredthe calorie content of food purchases for children andadolescents in four large fast-food chains before andafter mandatory labeling began in New York City. Although most of the adolescents reported noticing thecalorie labels, apparently the labels had no effect ontheir choices. Data similar to the results obtained showan average of M = 786 calories per meal with s =85 for n =100 children and adolescents before thelabeling, compared to an average of M = 772 calorieswith s = 91 for a similar sample of n = 100 after themandatory posting.a. Use a two-tailed test with a = .05 to determinewhether the mean number of calories after theposting is significantly different than before caloriecontent was posted.b. Calculate r2to measure effect size for the mean difference.
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