7th Edition

ISBN: 9780135901021

Author: Larson

Publisher: PEARSON EDUCATION (COLLEGE)

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Textbook Question

Chapter 8, Problem 3CT

A physical therapist suggests that soft tissue massage therapy helps to reduce the lengths of time patients suffer from headaches. The table shows the numbers of hours per day 18 patients suffered from headaches before and after 6 weeks of receiving treatment. At α = 0.05, is there enough evidence to support the therapist’s claim? Assume the populations are normally distributed. (Adapted from Annals of Musculoskeletal Medicine)

Chapter 8, Problem 3CT, A physical therapist suggests that soft tissue massage therapy helps to reduce the lengths of time

For each exercise, perform the steps below.

(a) Identify the claim and state H₀, and H_α.
(b) Determine whether the hypothesis test is left-tailed, right-tailed, or two-tailed, and whether to use a z-test or a t-test. Explain your reasoning.
(c) Find the critical value(s) and identify the rejection region (s).
(d) Find the appropriate standardized test statistic.
(e) Decide whether to reject or fail to reject the null hypothesis.
(f) Interpret the decision in the context of the original claim.

Features Features Normal distribution is characterized by two parameters, mean (µ) and standard deviation (σ). When graphed, the mean represents the center of the bell curve and the graph is perfectly symmetric about the center. The mean, median, and mode are all equal for a normal distribution. The standard deviation measures the data's spread from the center. The higher the standard deviation, the more the data is spread out and the flatter the bell curve looks. Variance is another commonly used measure of the spread of the distribution and is equal to the square of the standard deviation.

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Chapter 8, Problem 2CT

Chapter 8, Problem 4CT

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