PSY230
Summer B 2021
M4 Assignment (30 points)
General instruction:
1.
Complete the guided
Practice Problem
first, if you have not done so. It will help you become proficient in
answering the questions in this assignment.
2.
Check out the module,
Assignment Guides
,
which demonstrates how to show the math/process work and
provides instruction on essential procedures in Word and Excel, and APA formatting examples.
3.
Use this Word document to fill in the answers to the questions. You must type out a clear answer to each
question,
even if the answer is also contained in the Excel file submitted to show work
.
Q1)
One-Sample
t-
Test (11 points total)
I am shopping for a new sedan and would like to get one with excellent
miles per gallon
(MPG). I heard
that German cars tend to be more fuel efficient than American cars, so I collected MPG data on a
random sample of 10 German 4-cylinder sedan models (listed in the table below) to be compared to the
American car statistics. I would like to see if there is a significant difference, in either direction, between
German sedans and American sedans. The US Environmental Protection Agency reported that the
average MPG for American sedans in 2017 is
μ
= 30.6. I set the significance level at α = .10 for a two-
tailed hypothesis test.
Hint: Because we know the population mean for the American cars but not the standard deviation, we
cannot conduct a Z test but should perform a one-sample t-test instead.
chapter
MPG
1
30
2
29
3
29
4
36
5
33
6
32
7
30
8
25
9
35
10
33
a. Information about the hypothesis test:
- What is the dependent variable in this hypothesis test?
(.5 point)
- What is the “sample” for this one-sample
t
test?
(.5 point)
- What is the target population represented
by the sample
?
(.5 point)
- What is the comparison population?
(.5 point)

PSY230
Summer B 2021
b. What would be the null and alternative hypotheses in both words and symbol notations for my
analysis?
(1 point total: .5 for null and .5 for alternative. Both the written format and symbol notation
must be correct to get the .5 for a hypothesis)
c. Calculate the sample mean.