96. Preventing colds A medical experiment investigatedwhether taking the herb echinacea could help pre-vent colds. The study measured 50 different responsevariables usually associated with colds, such as low-grade fever, congestion, frequency of coughing, andso on. At the end of the study, those taking echinaceadisplayed significantly better responses at the a = 0.05level than those taking a placebo for 3 of the 50response variables studied. Should we be convincedthat echinacea helps prevent colds? Why or why not?

Answered: Image /qna-images/answer/4866582a-7c38-4af5-8981-ac00c9cd49ca.jpg

Answered: 96. Preventing colds A medical…

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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Q1: Placebo effect of exercise In a high-profile research study, Crum and Langer (2007) performed an experiment to test whether the relationship between physical exercise and health is impacted by one's mindset: in other words, if there is any "placebo effect" of exercise. A sample of 84 randomly selected hotel workers in the United States were placed either into a treatment group (n=44) or control group (n=40) depending on which hotel they worked at. The treatment group was given information demonstrating how their work is good physical exercise, while the control group was not given this information. They measured the body mass index (BMI) for each worker before the experiment and again four weeks after the experiment. a. Are the treatment group and control group independent of each other, and if so why? b. Now consider the treatment group alone: are the measurements of BMI taken before and after the experiment independent of each other, and if so why? c. What is the most appropriate…
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