The same clinician who was interested in the possibility of using ketamine to treat depression is conducting a follow-up study. This time she uses a between-subjects experimental design (comparing a treatment group to a control group). She injects a sample of n = 6 depressed individuals with ketamine and injects a second sample of n=8 with a saline solution. She administers Chapman's Revised Physical Anhedonia Scale (Chapman & Chapman, 1978; remember high scores mean less pleasure seeking) to both groups and compares their scores using an alpha level of a = .01. She predicts that the ketamine will again significantly lower the treatment sample's mean Anhedonia score. The data is presented below. a.) Step 1: State the Hypotheses H₂: H₂: Injection Type Control m₁-8 M=10.4 SS₁-1.65 Ketamine M-9.55 SS₂-1.87 b.) Step 2: Determine the critical region and draw it on the distribution above: df= _____ *critical = = تم c.) Step 3: Calculate the test statistic using the provided sample data: SM₁-M₂= tobs = d.) Step 4: Make a decision. Circle one: Reject Null (Ho) or e.) State your conclusions about the research scenario in sentence form: Fail to Reject Null (Ho) f.) Calculate an effect size in terms of the variance account for (2)? Do you characterize it as being small, medium or large?
The same clinician who was interested in the possibility of using ketamine to treat depression is conducting a follow-up study. This time she uses a between-subjects experimental design (comparing a treatment group to a control group). She injects a sample of n = 6 depressed individuals with ketamine and injects a second sample of n=8 with a saline solution. She administers Chapman's Revised Physical Anhedonia Scale (Chapman & Chapman, 1978; remember high scores mean less pleasure seeking) to both groups and compares their scores using an alpha level of a = .01. She predicts that the ketamine will again significantly lower the treatment sample's mean Anhedonia score. The data is presented below. a.) Step 1: State the Hypotheses H₂: H₂: Injection Type Control m₁-8 M=10.4 SS₁-1.65 Ketamine M-9.55 SS₂-1.87 b.) Step 2: Determine the critical region and draw it on the distribution above: df= _____ *critical = = تم c.) Step 3: Calculate the test statistic using the provided sample data: SM₁-M₂= tobs = d.) Step 4: Make a decision. Circle one: Reject Null (Ho) or e.) State your conclusions about the research scenario in sentence form: Fail to Reject Null (Ho) f.) Calculate an effect size in terms of the variance account for (2)? Do you characterize it as being small, medium or large?
MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
Related questions
Question

Transcribed Image Text:The same clinician who was interested in the possibility of using ketamine to treat depression is conducting
a follow-up study. This time she uses a between-subjects experimental design (comparing a treatment group
to a control group). She injects a sample of n = 6 depressed individuals with ketamine and injects a second
sample of n = 8 with a saline solution. She administers Chapman's Revised Physical Anhedonia Scale (Chapman
& Chapman, 1978; remember high scores mean less pleasure seeking) to both groups and compares their scores using an alpha
level of a = .01. She predicts that the ketamine will again significantly lower the treatment sample's mean
Anhedonia score. The data is presented below.
a.) Step 1: State the Hypotheses
Ho:
H₁:
Injection Type
*critical
SM₁-M₂
Control
1₁-8
M=104
SS₁-1.65
b.) Step 2: Determine the critical region and draw it on the distribution above:
df =
Ketamine
-6
M-9.55
SS₂ -1.87
c.) Step 3: Calculate the test statistic using the provided sample data:
tobs =
d.) Step 4: Make a decision.
e.) State your conclusions about the research scenario in sentence form:
Circle one: Reject Null (Ho) or Fail to Reject Null (Ho)
f.) Calculate an effect size in terms of the variance account for (²2)? Do you characterize it as being
small, medium or large?

Transcribed Image Text:A researcher conducts a between-subjects study to determine whether low levels of the neurochemical
serotonin leads to an increase in aggression. One sample of rats serves as a control group and receives a
placebo that does not affect normal levels of serotonin. A second sample of rats receives a drug that lowers
brain levels of serotonin. Using an alpha level of a = .05, the researcher then tests the animals by recording
the number of aggressive responses each of the rats display. The data are as follows:
a.) Step 1: State the Hypotheses
Ho:
H₁:
Control
n = 10
M = 14
SS=180.5
b.) Step 2: Determine the critical region and draw it on the distribution above:
df =
> *critical
SM₁-M₂
Low Serotonin
n = 15
M = 19
SS = 130.0
c.) Step 3: Calculate the test statistic using the provided sample data:
tobs
d.) Step 4: Make a decision. Circle one: Reject Null (Ho) or Fail to Reject Null (Ho)
e.) State your conclusions about the research scenario in sentence form:
d=
f.) What is the estimated effect size (Cohen's d) in this study? Do you characterize it as being small,
medium or large?
Expert Solution

This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
Step by step
Solved in 3 steps

Recommended textbooks for you

MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc

Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning

MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc

Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning

Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning

Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON

The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman

Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman