Essentials of Statistics for the Behavioral Sciences
8th Edition
ISBN: 9781133956570
Author: Frederick J Gravetter, Larry B. Wallnau
Publisher: Cengage Learning
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Textbook Question
Chapter 9, Problem 14P
The librarian at the local elementary school claims that, on average, the books in the library are more than 20 years old. To test this claim, a student takes a sample of n = 30 books and records the publication date for each. The sample produces an average age of M = 23.8 years with a variance of s2 = 67.5. Use this sample to conduct a one-tailed test with
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The librarian at the local elementary school claims that, on average, the books in the library are more than 20 years old. To test this claim, a student takes a sample of n =30 books and records the publication date for each. The sample produces an average age of M = 23.8 years with a variance of S2 = 67.5. Use this sample to conduct a one-tailed test with α= .01 to determine whether the average age of the library books is significantly greater than 20 years (μ> 20).
Chapter 9 Solutions
Essentials of Statistics for the Behavioral Sciences
Ch. 9.1 - Under what circumstances is a t statistic used...Ch. 9.1 - A sample of n = 9 scores has SS = 288. a. Compute...Ch. 9.1 - Prob. 3LCCh. 9.1 - Prob. 4LCCh. 9.1 - For df = 15, find the value(s) of t associated...Ch. 9.2 - A sample of n = 4 individuals is selected from a...Ch. 9.3 - If all other factors are held constant, an 80%...Ch. 9.3 - If all other factors are held constant, a...Ch. 9.3 - Prob. 1LCACh. 9.3 - How does sample size influence the outcome of a...
Ch. 9.4 - A new over-the-counter cold medication includes a...Ch. 9 - Under what circumstances is a t statistic used...Ch. 9 - A sample of n = 25 scores has a mean of M = 83 and...Ch. 9 - Find the estimated standard error for the sample...Ch. 9 - Explain why t distributions tend to be flatter and...Ch. 9 - Find the t values that form the boundaries of the...Ch. 9 - The following sample of n = 6 scores was obtained...Ch. 9 - The following sample was obtained from a...Ch. 9 - A random rumple of n = 25 individuals is selected...Ch. 9 - To evaluate the effect of a treatment, a sample is...Ch. 9 - To evaluate the effect of a treatment, a sample of...Ch. 9 - The spotlight effect refers to overestimating the...Ch. 9 - Many animals, including humans, tend to avoid...Ch. 9 - Standardized measures seem to indicate that the...Ch. 9 - The librarian at the local elementary school...Ch. 9 - For several years researchers have noticed that...Ch. 9 - Weinstein, McDermott, and Roediger (2010) report...Ch. 9 - Ackerman and Goldsmith (2011) found that students...Ch. 9 - A random sample of n = 16 scores is obtained from...Ch. 9 - A random sample is obtained from a population with...Ch. 9 - An example of the vertical-horizontal illusion is...Ch. 9 - McGee and Shevlin (2009) demonstrated that an...Ch. 9 - Oishi and Shigehiro (2010) report that people who...Ch. 9 - Prob. 23P
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