
MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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Question
A school psychologist is interested in determining if children with attention deficit hyperactivity disorder (ADHD) learn better if English literature is read to them rather than having them read the material alone by themselves. A random sample of 10 sixth graders with ADHD is selected and divided into two groups of n=9. One of the groups has a story read to them (Listening Group) and the other reads the story alone by themselves (Reading Group). A test on the story is given after each group has finished reading or hearing the story. The following scores were obtained with 20 being a perfect score.
What is the alpha level?

Transcribed Image Text:t-Test: Two-Sample Assuming Equal Variances
G1
G2
Mean
8.777777778
11.44444444
Variance
3.944444444
3.277777778
Observations
9.
9.
Pooled Variance
3.611111111
Hypothesized Mean
df
16
t Stat
-2.97683363
P(T<=t) one-tail
0.004449553
t Critical one-tail
1.745883676
P(T<=t) two-tail
t Critical two-tail
0.008899105
2.119905299
@
#
24
8.
9.
6.
2
y
u
W
e
h

Transcribed Image Text:Two-sample t-test, independent groups
Reading Group
Listening Group
10
15
10
12
7
13
12
11
8
10
9.
10
11
9.
10
11
11
Count(n)
Mean
DEVSQ(SS)
STDEV.S
df
S(M1-M2)
alpha
tcrit
Reject Ho
Fail to reject Ho
tobs
Decision
Cohen's d
&
@
23
$
%
6
8
3.
4
r
y
e
h
k
f
n.
m
C
V
6.0
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