Essentials of Statistics for The Behavioral Sciences (MindTap Course List)
9th Edition
ISBN: 9781337098120
Author: Frederick J Gravetter, Larry B. Wallnau, Lori-Ann B. Forzano
Publisher: Cengage Learning
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Textbook Question
Chapter 9, Problem 15P
Weinstein, McDermott, and Roediger (2010) report that students who were given questions to be answered while studying new material had better scores when tested on the material compared to students who were simply given an opportunity to reread the material. In a similar study, a group of students from a large psychology class were given questions to be answered while studying for the final exam. The overall average for the exam was μ = 73.4 but the n = 16 students who answered questions had a mean of M = 78.3 with a standard deviation s = 8.4. Use a two-tailed test with α = .01 to determine whether answering questions while studying produced significantly higher exam scores.
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Chapter 9 Solutions
Essentials of Statistics for The Behavioral Sciences (MindTap Course List)
Ch. 9.1 - In what circumstances is the t statistic used...Ch. 9.1 - A sample of n = 4 scores has SS = 48. What is the...Ch. 9.1 - On average, what value is expected for the t...Ch. 9.2 - A sample of n = 9 scores is selected from a...Ch. 9.2 - A hypothesis test produces a t statistic of t =...Ch. 9.2 - A sample is selected from a population and a...Ch. 9.3 - A sample of n = 25 is selected from a population...Ch. 9.3 - Prob. 2LCCh. 9.3 - A sample of n = 4 scores is selected from a...Ch. 9.3 - A researcher uses a sample of n = 25 individuals...
Ch. 9.4 - A sample is selected from a population with a mean...Ch. 9.4 - A researcher predicts that a treatment will...Ch. 9.4 - A researcher fails to reject the null hypothesis...Ch. 9 - Under what circumstances is a t statistic used...Ch. 9 - A sample of n = 16 scores has a mean of M = 56 and...Ch. 9 - Find the estimated standard error for the sample...Ch. 9 - The following sample of n = 4 score was obtained...Ch. 9 - The following sample was obtained from a...Ch. 9 - Explain why t distributions tend to be flatter and...Ch. 9 - Find the t values that form boundaries of the...Ch. 9 - Find the t value that forms the boundary of the...Ch. 9 - A random sample n = 12 individuals is selected...Ch. 9 - A random sample of n 4 individuals is selected...Ch. 9 - Infants, even newborns, prefer to look at...Ch. 9 - The spotlight effect refers to overestimating the...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 - Weinstein, McDermott, and Roediger (2010) report...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 - Standardized measures seem to indicate that the...Ch. 9 - Ackerman and Goldsmith (2011) found that students...Ch. 9 - Oishi and Shigehiro (2010) report that people who...Ch. 9 - McGee and Shevlin (2009) demonstrated that an...Ch. 9 - Belsky, Weinraub, Owen, and Kelly (2001) reported...Ch. 9 - An example of the vertical-horizontal illusion is...
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