## Transcribed Text

1
Suppose you the multiple regression model
60+ 63x1 62x2 + €
ton O data points and obtain the following result: 9 3.4 4.6x1 2.7x2 -0-93x,
The estimated standard errors B, and B, are 1.86 and 29, ,respectively.
a. Test the nul hypothesis Ho 6, Dagainst the alternative hypothesis He 62 =0. Usea
.05.
Test the null hypothesis Ho 63=Dagainst the alternative hypothesis He 6, 0. Use a
.05.
The null hypothesis Ho: 62= Ois not rejected In contrast, the null hypothesis Ho: 6:=
Ois rejected Explain how thiscanhappen even though B2 >B
2. Use SPSSt fita second order model the following data
x
3
4
5
6
y
2.7
3.8
4.5
5.0
5.3
5.2
a.
Find SSE ands².
b
Do data provide sufficient evidence to indicate that the second -or der term
provides information for the prediction of y? [Hint: Test Ho: 62 =0].
c.
State the least squares prediction equation
3. Running manufacturing operation efficiently requires knowledge of the time takes
employees to manufacture the product otherwise the cost of making the product
cannot br determined Estimates o production time are frequently obtained using time
studies. The datair the table below carne from arecent time study of sampleo 15
employees performing particular task on an automobile assembly line
Time
Assemble,
Months
(minutes)
Experience, x
10
24
15
11
15
11
17
19
11
20
13
17
18
16
16
a.
Run the multiple linear regression model ir SPSS. State the least squares
prediction equation
b
Test 6: the alternative He .01
Does the term tothe model?
c. Your conclusion drop quadratic term from
the
model. Doso the 6xx+tothe data.
d. Define Bain exercise. Find 90% confidence interval for in
thereducedmodelof part c.
4.
Suppose you fit the modely 60 61x1 62X2- 63X1X2 64x2+
datapoints and get SSE .46andR²= 87.
a. Do the values SSE and 'suggest that the model provides good f tothe
data? Explain.
b. Is the model of any usei predicting /? Test the nul hypothesis that E(y)=60;
that
Ho:62=62=63=64=65=0
against the alternative hypothesis
Ha: least one of the parameters 6, 62, 6sis nonzero
Use 05.
5. company that services copy machines interested developing regression model
that will assist in personnel planning tneeds amodel that describes the relationship
between thetime spent on preventive maintenance service call to a customer, and
two independent variables: the number of copy machines be serviced, X1, and the
service person's experience preventive maintenance, X2.
Hours of
Number
Months
maintenance
copy machines
experience
1.0
12
17.0
10
14.0
6.0
10
1.8
11.5
10
10
9.3
6.0
6
12.2
10
18
a.
Fit the modely 60 62% 62X; + € tothe data.
b Investigate whether the model useful. Test .10
c.
Find for the fitted model. Interpret your results
d. Fit the model y €tothe data
Find for themodel ir part d
Explain why ou should not relv solel on comparison of the two R² values for
drawing conclusions about which model smore useful for predicting
g.
Do the data provide sufficient evidence indicate that the interaction term
X1X2
contributes information for the prediction ofy? Hint: Test Ha 6, 01 Which
modeli: more usefu for predicting v?
h.
Can you be certain that the model you selected inpart best model
use
inpredicting maintenance time Explain.

These solutions may offer step-by-step problem-solving explanations or good writing examples that include modern styles of formatting and construction
of bibliographies out of text citations and references. Students may use these solutions for personal skill-building and practice.
Unethical use is strictly forbidden.