Callahan (2009) demonstrated that tai chi can signifi- cantly reduce symptoms for individuals with arthritis. Participants were 18 years old or older with doctor- diagnosed arthritis. Self-reports of pain and stiffness were measured at the beginning of an eight-week tai chi course and again at the end. Suppose that the data produced an average decrease in pain and stiffness of MD = 8.5 points with a standard deviation of 21.5 for a sample of n = 40 participants. Use a two-tailed test with a = .05 to determine whether the tai chi had a significant effect on pain and stiffness. Compute Cohen’s d to measure the size of the treatment effect.

Callahan (2009) demonstrated that tai chi can signifi- cantly reduce symptoms for individuals with arthritis. Participants were 18 years old or older with doctor- diagnosed arthritis. Self-reports of pain and stiffness were measured at the beginning of an eight-week tai chi course and again at the end. Suppose that the data produced an average decrease in pain and stiffness of MD = 8.5 points with a standard deviation of 21.5 for a sample of n = 40 participants. Use a two-tailed test with a = .05 to determine whether the tai chi had a significant effect on pain and stiffness. Compute Cohen’s d to measure the size of the treatment effect.

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Description: Callahan (2009) demonstrated that tai chi can signifi- cantly reduce symptoms for individuals with arthritis. Participants were 18 years old or older with doctor- diagnosed arthritis. Self-reports of pain and stiffness were measured at the beginning

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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