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 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 onetailed test with a = .05. b. Compute the 80% confidence interval for the mean change 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 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 onetailed test with a = .05. b. Compute the 80% confidence interval for the mean change in attention span for the population.

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Description: The stimulant Ritalin has been shown to increase attention span and improve academic performance in children with ADHD (Evans et al., 2001). To demonstratethe effectiveness of the drug, a researcher selects asample of n = 20 children diagnosed with t

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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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.
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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 ofn=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=4.8minutes 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. Compute the 80% confidence interval for the mean change in attention span for the population.
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