NorthWest Arkansas Community College Regression Statistics Exam Practice

QUESTION 1

Given the data below, a researcher would like to know whether someone’s age group affects their choice of toilet paper brand.

Observed
Brand A Brand B Brand C Sum
Teen 120 130 110 360
Mid-Age 77 127 140 344
Senior 84 100 98 282
281 357 348 986

A complete answer should:

Indicate which test she should use.
State hypotheses
Report if the test was significant and what decision is made
Run any necessary post-hoc analysis (and paste the result in the answer)
Provide a conclusion sentence and the statistics in APA format.

QUESTION 2

A tutor measures her students with a 5 point algorithm, and she would like to know if her 6 students improved this month.

Student Day 1 Day 30
A 2.4 3.0
B 2.5 2.8
C 3.0 2.9
D 2.9 2.4
E 2.7 3.5
F 2.1 2.9

A complete answer should:

Indicate which test she should use.
State hypotheses
Report if the test was significant and what decision is made
Provide a conclusion sentence and the statistics in APA format.

QUESTION 3:

For the following output, write a paragraph (3-4 sentences) discussing the result. Your paragraph should indicate:

What test was used
What the test measures
Whether the test is significant
What the result/decision was in terms of the variables and if any additional testing is necessary.
Report the statistics in APA format.
Make a statement of conclusion about what a researcher would learn from this result. (You may create what causes the differences in groups such as: location, worksheets, demographics, etc.)

SUMMARY OUTPUT

Regression Statistics
Multiple R 0.237673
R Square 0.056489
Adjusted R Square 0.015466
Standard Error 20.51556
Observations 25

ANOVA
df SS MS F Significance F
Regression 1 579.5726 579.5726 1.377023 0.252618
Residual 23 9680.427 420.8881
Total 24 10260

Coefficients Standard Error t Stat P-value Lower 95% Upper 95% Lower 95.0% Upper 95.0%
Intercept 63.68956 6.886156 9.248928 3.27E-09 49.44446 77.93465 49.44446 77.93465
Absences -1.72595 1.47081 -1.17347 0.252618 -4.76855 1.316657 -4.76855 1.316657

QUESTION 4

For the following output, write a paragraph (3-4 sentences) discussing the result. Your paragraph should indicate:

What test was used
What the test measures
Whether the test is significant
What the result/decision was in terms of the variables and if any additional testing is necessary.
Report the statistics in APA format.

Observed Values Expected Values
Attended Did Not Attend Sum Attended Did Not Attend
Joined 10 12 22 Joined 6.695652 15.30435
Did Not Join 4 20 24 Did Not Join 7.304348 16.69565
14 32 46

Observed Expected (O-E)2 (O-E)2 /E
Joined and Attended 10 6.695652174 10.91871 1.630717
Did Not Join and Did Not Attend 12 15.30434783 10.91871 0.713439
Joined and Attended 4 7.304347826 10.91871 1.494824
Did Not Join and Did Not Attend 20 16.69565217 10.91871 0.653986
X2 4.492965

P Value 0.034035

QUESTION 5

A principal wanted to know if the location of testing affected student performance on a statewide standardized test. He collected the following data:

Control 60 degrees Classical Music Next to Cafeteria
31 53 27 29
16 39 36 18
11 71 32 16
19 39 14 20
43 54 40 7
49 41 60 12
4 9 47 20
11 17 2 45
34 13 27 33
39 8 5 53
60 32 55 23
40 29 53 24
57 35 27 18
59 45 4 49
43 42 50 29

A complete answer should:

Indicate which test should be used.
State hypotheses
Report if the test was significant and what decision is made
Provide a conclusion sentence and the statistics in APA format.

QUESTION 6

For the following output, write a paragraph (3-4 sentences) discussing the result. Your paragraph should indicate:

What test was used
What the test measures
Whether the test is significant
What the result/decision was in terms of the variables and if any additional testing is necessary.
Report the statistics in APA format.
Make a statement of conclusion about what a researcher would learn from this result.
SUMMARY
Groups Count Sum Average Variance
Group 1 25 1467 58.68 253.2267
Group 2 25 1525 61 628.75
Group 3 25 1592 63.68 403.2267

Source of Variation SS df MS F P-value F crit
Between Groups 7698.107 2 3849.053 8.984695 0.000329 3.123907
Within Groups 30844.88 72 428.4011

Total 38542.99 74

QUESTION 7

Given the data below, does the number of minutes spent exercises affect the number of glasses of water a person consumes?

Glasses of Water Minutes
1 50
1 27
1 25
2 67
2 25
2 50
3 80
3 33
3 15
3 76
3 38
3 41
3 22
4 84
4 67
4 69
4 81
4 55

A complete answer should:

Indicate which test she should use.
Report if the test was significant and what decision is made
Provide a conclusion sentence and the statistics in APA format.

QUESTION 8

For the following output, write a paragraph (3-4 sentences) discussing the result. Your paragraph should indicate:

What test was used
What the test measures
Whether the test is significant
What the result/decision was in terms of the variables and if any additional testing is necessary.
Report the statistics in APA format.
Make a statement of conclusion about what a researcher would learn from this result. (You may create what causes the differences in groups such as: location, worksheets, demographics, etc.)
Two-Sample Assuming Unequal Variances

Group 1 Group 2
Mean 61.90909 49.64
Variance 341.5152 472.9067
Observations 22 25
Hypothesized Mean Difference 0
df 45
t Stat 2.090657
P(T<=t) one-tail 0.021119
t Critical one-tail 1.679427
P(T<=t) two-tail 0.042237
t Critical two-tail 2.014103

QUESTION 9

For the following output, write a paragraph (3-4 sentences) discussing the result. Your paragraph should indicate:

What test was used
What the test measures
Whether the test is significant
What the result/decision was in terms of the variables and if any additional testing is necessary.
Report the statistics in APA format.
Make a statement of conclusion about what a researcher would learn from this result. (You may create what causes the differences in groups such as: location, worksheets, demographics, etc.)

t-Test: Paired Two Sample for Means

Group 1 Group 2
Mean 67 84.38461538
Variance 423.1666667 209.4230769
Observations 13 13
Pearson Correlation 0.129328052
Hypothesized Mean Difference 0
df 12
t Stat -2.659252971
P(T<=t) one-tail 0.010410066
t Critical one-tail 1.782287556
P(T<=t) two-tail 0.020820131
t Critical two-tail 2.17881283