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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Chapter 11, Problem 10P
The stimulant Ritalin has been shown to increase attention span and improve academic performance in children with ADHD (Evans et al., 2001). To demonstrate the effectiveness of the drug, a researcher selects a sample of n – 20 children diagnosed with the disorder and measure each child’s attention span before and after taking the drug. The data show an average increase of attention span of MD = 4.8 minutes with a variance of s2 – 125 for the sample of difference scores.
a. Is this result sufficient to conclude that Ritalin significantly improves attention span? Use a one tailed test with α = .05.
b. Compute the 80% confidence interval for the mean change in attention span for the population.
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Ritalin has been shown to increase attention span and improve academic performance in children with ADHD (Evans et al., 2001). To demonstrate the effectiveness of the drug, a researcher selects a sample of n = 20 children diagnosed with ADHD and measures each child’s attention span before and after taking the drug. The data show an average increase of attention span of MD = 4.8 minutes with a variance of s2 = 125 for the sample of difference scores.
Is this result sufficient to conclude that Ritalin significantly improves attention span? Use a one-tailed test at .05.
Compute the 80% confidence interval for the mean chance in attention span for the population.
The stimulant Ritalin has been shown to increase attention span and improve academic performance in children with ADHD (Evans et al., 2001). To demonstrate the effectiveness of the drug, a researcher selects a sample of n = 20 children diagnosed with the disorder and measures each child’s attention span before and after taking the drug. The data show an average increase of attention span of MD= 4.8 with a variance of s2 = 125 for the sample of difference scores. Is this result sufficient to conclude that Ritalin significantly improves attention span? Use a one-tailed test with α = .05.
Female college student participation in athletics has increased dramatically over the past few decades. Sports medicine providers are aware of some unique health concerns of athletic women, including disordered eating. A study compared disordered-eating symptoms and their causes for collegiate female athletes (in lean and non lean sports) and nonathletes. The sample mean of the body dissatisfaction assessment score was 13.4 (s=7.9) for 15 lean sports athletes (those sports that place value on leanness, including distance running, swimming, and gymnastics) and 7.4 (s=5.8) for the 67 non-lean athletes. Assume equal population standard deviations.
Find the standard error for comparing the means.
Construct a 95% confidence interval for the difference between the mean body dissatisfaction for lean sport athletes and non lean sport athletes. Interpret.
Chapter 11 Solutions
Essentials of Statistics for The Behavioral Sciences (MindTap Course List)
Ch. 11.1 - In a repeated-measures study, the same group of...Ch. 11.1 - A researcher conducts a research study comparing...Ch. 11.1 - For an experiment comparing two treatment...Ch. 11.2 - What is the mean for the difference scores for the...Ch. 11.2 - Which of the following is the correct statement of...Ch. 11.2 - Which of the following accurately describes the...Ch. 11.2 - Prob. 4LCCh. 11.3 - A researcher conducts a repeated-measures study...Ch. 11.3 - Prob. 2LCCh. 11.4 - Prob. 1LC
Ch. 11.4 - Prob. 2LCCh. 11.4 - A research report describing the results from a...Ch. 11.4 - Prob. 4LCCh. 11.4 - Prob. 5LCCh. 11.5 - Which of the following possibilities is a concern...Ch. 11.5 - For which of the following situations would an...Ch. 11.5 - Prob. 3LCCh. 11 - For the each of the following studies determine...Ch. 11 - What is the defining characteristic of a...Ch. 11 - A researcher conducts an experiment comparing two...Ch. 11 - A repeated-measures and an independent-measures...Ch. 11 - A sample of n = 16 individuals participates in a...Ch. 11 - Resenhoeft, Villa, and Wiseman (2008) conducted a...Ch. 11 - The following data are from a repeated-measures...Ch. 11 - When you get a surprisingly low price on a product...Ch. 11 - Masculine-themed words (such us competitive,...Ch. 11 - The stimulant Ritalin has been shown to increase...Ch. 11 - College athletes, especially males, are often...Ch. 11 - Callahan (2009) demonstrated that tai chi can...Ch. 11 - Research results indicate that physically...Ch. 11 - There is some evidence suggesting that you are...Ch. 11 - In Example 8.1 (page 200) we discussed a research...Ch. 11 - Solve the following problems. a. A...Ch. 11 - Solve the following problems. a. A...Ch. 11 - A sample of difference stores from a...Ch. 11 - Participants enter a research study with unique...Ch. 11 - Swearing is a common, almost reflexive, response...Ch. 11 - The previous problem demonstrates that removing...Ch. 11 - Explain the difference between a matched-subjects...Ch. 11 - A researcher conducts an experiment comparing two...Ch. 11 - A repeated-measures, a matched-subjects, and an...
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