A researcher conducts a between-subjects study to determine whether low levels of the neurochemicalserotonin leads to an increase in aggression. One sample of rats serves as a control group and receives aplacebo that does not affect normal levels of serotonin. A second sample of rats receives a drug that lowersbrain levels of serotonin. Using an alpha level of a = .05, the researcher then tests the animals by recordingthe number of aggressive responses each of the rats display. The data are as follows:Step 1: State the HypothesesHo:H₂:Controln = 10M-14SS = 180.5Step 2: Determine the critical region and draw it on the distribution above:df =teriticalLow Serotoninn = 15M=19SS = 130.0Step 3: Calculate the test statistic using the provided sample data:d=SM₁tobeStep 4: Make a decision. Circle one: Reject Null (Ho) orState your conclusions about the research scenario in sentence form:Fail to Reject Null (H₂)What is the estimated effect size (Cohen's d) in this study? Do you characterize it as being small,medium or large?

Answered: Image /qna-images/answer/575df609-0542-4fa5-941d-79ba2b49dc26.jpg

Answered: A researcher conducts a…

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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