10th Edition

ISBN: 9780321989178

Author: Neil A. Weiss

Publisher: PEARSON

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When we calculate intervals in probability and statistics, it can be simply termed as finding out a confidence interval. The confidence interval is usually calculated from the data set which is observed. The value of the parameter that needs to be calcul…

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Textbook Question

Chapter 8.2, Problem 77E

Medical Marijuana. An issue with legalization of medical marijuana is “diversion” the process in which medical marijuana prescribed for one person is given, traded, or sold to someone who is not registered for medical marijuana use. Researchers S. Sautel el al. study the issue of diversion in the article “Medical Marijuana Use Among Adolescents in Substance Abuse Treatment” (Journal of the American Academy of Child and Adolescent Psychiatry, Vol. 51, No. 7, pp. 694–702), The mean number of days that 120 adolescents in substance abuse treatment used medical marijuana in the last 6 months was 102.72. Assume the population standard deviation is 32 days.

a. Find a 95% confidence interval for the mean number of days, μ, of diverted medical marijuana use in the last 6 months of all adolescents in substance abuse treatment.
b. Repeat part (a) at a 90% confidence level.
c. Draw a graph similar to Fig. 8.6 on page 343 to display both confidence intervals.
d. Which confidence interval yields a more accurate estimate of μ? Explain your answer.

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 8.2, Problem 76E

Chapter 8.2, Problem 78E

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Chapter 8 Solutions

Introductory Statistics (10th Edition)

Ch. 8.1 - The value of a statistic used to estimate a...Ch. 8.1 - What is a confidence-interval estimate of a...Ch. 8.1 - Prob. 3E Ch. 8.1 - Prob. 4E Ch. 8.1 - Prob. 5E Ch. 8.1 - Suppose that you lake 500 simple random samples...Ch. 8.1 - Prob. 7E Ch. 8.1 - A simple random sample is taken from a population...Ch. 8.1 - Refer to Exercise 8.7 and find a point estimate...Ch. 8.1 - Prob. 10E

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Solution Summary: The author explains the 95% confidence interval for the population mean number of days based on adolescents in substance abuse treatment using medical marijuana.

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