CSUSM Smoking and GPA Analysis
Business Statistics 304
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Walter Evans
Farzana Mohsini
Sheryl Lejano
Ryan Thomas
Three Reasons
• Students smoke for
pleasure.
• Students’ smoking
habits may be tied to a
person’s family history.
• Smoking may depend
of student age and
knowledge .
Mission Statement
• Smoking has a negative, positive or neutral impact on the success of
students.
• Our analysis will assist us in planning and implementing smoking
intervention programs for Cal State San Marcos.
• Programs may be helpful in preventing the habit of tobacco use in school.
• Help us take action in making an effort to inform the council and promote a
lesser degree of smoking on campus.
• Our group would like to determine whether or not smoking on campus is
decreasing or increasing and why that is so.
• To properly evaluate the extensiveness of a student smoker’s habits and
the level of success a student has accomplished.
Cal State San Marcos Smoking Survey
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Gender:
Male
Female
Class:
Freshman
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What is your G.P.A.?
Sophomore
Age:
17-20
21-24
What is your major? _____________
<= 2.0
2.01~2.4
Do you have a family history of smoking?
When I see a person smoking, it…
makes him/her more attractive.
makes him/her less attractive
has no impact on their attractiveness.
Would you date a person who is smoker?
25-28
Junior
Senior
29-32
33-36
2.41~2.80
2.81~3.20
YES
NO
3.21~3.60
YES
37-40
>3.6
NO
Do you smoke tobacco?
YES
NO
If YES, how many times do you smoke a day?
1-3 times
4-6 times
How long have you been smoking? < 1 year
7-9 times
1-3 years
3-10 years >10 years
Thank you for your help on this research project! It is greatly appreciated!
>10 times
>40
Excel Spreadsheet Set-up
# Gender Class Age Major G.P.A. History Attractiveness Date? Smoke Per Day Years
Related Information
• Causes for Smoking.
• Time of day (cigarettes/day)
• Duration of smoking
• Family History of smoking
• Student smoking percentage
• number of student smokers
• Given the nature and the student lifestyle, we expect 17% of our
surveyed sample to be smokers.
• Proceed in our research by surveying 105 students on campus to
operate as a sample for the standard population of the school.
Background Information/Factors
• Health risks (first and second hand)
• Cancer susceptibility
• based on time spent on campus in direct connection with smoking
• Comparing and contrasting smoker comfort versus non-smoker
discomfort
• Non-smokers hidden annoyances toward smoking
• Smoker’s Nonsmokers awareness of nonsmokers smokers
• Determining possible reasons for smoking (stress, habit, social
conformity?)
Mean, Variance, Frequency and Mode
Mean for Age
• Used midpoints
• Total, Non-Smoking, & Smoking
Mean Total Students
Mean Non-Smoking
Mean Smoking
Age
# of Students
Age
# of Students
Age
# of Students
18.5
20
18.5
15
18.5
5
22.5
57
22.5
52
22.5
5
26.5
14
26.5
11
26.5
3
30.5
7
30.5
6
30.5
1
34.5
0
34.5
0
34.5
0
38.5
1
38.5
0
38.5
1
>40
5
>40
5
>40
0
Mean
23.80288462
Mean
23.84269663
Mean
23.56666667
Mean, Variance & Standard Deviation for GPA
• Used Midpoints
• Total, Non-Smoking, & Smoking
Mean GPA Total
< 2.0
0
2.205
3
2.605
21
3.005
25
3.405
44
> 3.6
11
Mean
Variance
Std Dev
3.133317308
Mean GPA NonSmoking
< 2.0
0
2.205
2
2.605
16
3.005
21
3.405
39
> 3.6
11
Mean
Variance
Std Dev
3.163932584
Mean GPA Smoking
< 2.0
0
2.205
1
2.605
5
3.005
4
3.405
5
> 3.6
0
Mean
2.951666667
Variance
Std Dev
Mean Standard Deviation and Frequency
Frequency Distribution of Age (Total)
57
60
50
40
30
20
20
14
7
10
0
1
33-36
37-40
0
17-20
21-24
25-28
29-32
Mean = 23.80288462
Standard Deviation = 5.026830087
5
>40
Mean Standard Deviation and Frequency
Frequency Distribution of Age (Non-Smoking)
60
52
50
40
30
20
15
11
10
6
0
17-20
21-24
25-28
29-32
0
0
33-36
37-40
Mean = 23.84269663
Standard Deviation = 4.966704771
5
>40
Mean Standard Deviation and Frequency
Frequency Distribution of Age (Smoking)
6
5
5
5
4
3
3
2
1
1
1
0
0
17-20
21-24
25-28
29-32
33-36
Mean = 23.56666667
Standard Deviation = 5.548058433
0
37-40
>40
Mean Standard Deviation and Frequency
Frequency Distribution of GPA (Total)
45
40
35
30
25
20
15
10
5
0
42
27
21
11
0
<=2.0
3
2.01-2.40
2.41-2.80
2.81-3.20
Mean = 3.133317308
Standard Deviation = 0.37522654
3.21-3.60
> 3.60
Mean Standard Deviation and Frequency
Frequency Distribution of GPA (Non-Smoking)
40
35
30
25
20
15
10
5
0
37
23
16
11
0
2
<=2.0
2.01-2.40
2.41-2.80
2.81-3.20
Mean = 3.163932584
Standard Deviation = 0.365036947
3.21-3.60
> 3.60
Mean Standard Deviation and Frequency
Frequency Distribution of GPA (Smoking)
6
5
5
5
4
4
3
2
1
0
1
0
<=2.0
0
2.01-2.40
2.41-2.80
2.81-3.20
Mean = 2.951666667
Standard Deviation = 0.396172161
3.21-3.60
> 3.60
Mean Standard Deviation and Frequency
Frequency Distribution of Cigarettes per Day
8
7
6
5
4
3
2
1
0
7
3
2
1
1 to 3
4 to 6
7 to 9
Mean = 4.769230769
Standard Deviation = 3.491748515
> 10
Mean Standard Deviation and Frequency
Frequency Distribution of Years Smoking
6
5
5
4
4
4
3
2
1
1
0
< 1 year
1 to 3 years
3 to 10 years
Mean = 3.4
Standard Deviation = 3.10617959
> 10 years
Mean Standard Deviation and Frequency
Frequency Distribution of Family History (Total)
55
54
54
53
52
51
50
50
49
48
Yes
No
Mean Standard Deviation and Frequency
Frequency Distribution of Family History (Non-Smoking)
47
46
46
45
44
44
43
Yes
No
Mean Standard Deviation and Frequency
Frequency Distribution of Family History (Smoking)
12
10
10
8
6
4
4
2
0
Yes
No
Mean Standard Deviation and Frequency
Frequency Distribution of Attractiveness (Total)
90
80
70
60
50
40
30
20
10
0
80
20
2
1
More Attractive
Less Attractive
No Impact
Other
Mean Standard Deviation and Frequency
Frequency Distribution of Attractiveness (Non-Smoking)
80
70
60
50
40
30
20
10
0
77
10
1
More Attractive
Less Attractive
No Impact
2
Other
Mean Standard Deviation and Frequency
Frequency Distribution of Attractiveness (Smoking)
12
10
8
6
4
2
0
10
3
0
More Attractive
Less Attractive
No Impact
Mean Standard Deviation and Frequency
Frequency Distribution of Dating a Smoker (Total)
90
80
70
60
50
40
30
20
10
0
77
25
Yes
No
Mean Standard Deviation and Frequency
Frequency Distribution of Dating a Smoker (Non-Smoking)
80
70
60
50
40
30
20
10
0
74
14
Yes
No
Mean Standard Deviation and Frequency
Frequency Distribution of Dating a Smoker (Smoking)
12
11
10
8
6
4
3
2
0
Yes
No
Conditional Probability
Conditional Probability Rules:
15 Smokers
11 Smoker Male
4 Smoker Female
Total Population: 43 Female
62 Males
Continuous Variables
Probability Rule 4: Addition Rule for Any Two Events,
E1 and E2 P(E1 or E2)=P(E1)+P(E2)-P(E1 and E2).
90 Nonsmokers
Mutually Exclusive Events
E1
E2
Probability Rule 5: Addition Rule for Mutually
Exclusive Events
Two Mutually Exclusive Events E1 and E2
Conditional Probability
Table 1.
Smoker
Male
Nonsmoker
11
Female
51 Total 105
4
39
Table 2.
GPA>3.0
GPA<3.0
Smoking Male
7
4 Total 15 Smokers
Smoking Female
2
2
Graphical Representation
Smoking Males Vs GPA
8
7
6
5
4
3
2
1
0
GPA<3.0
GPA>3.0
GPA>3.0 GPA<3.0
Smoking Male
Smoking Female
7
2
4Total 15 Smokers
2
Graphical Representation
Smoking Females Vs GPA
2.5
2
1.5
GPA<3.0
GPA>3.0
1
0.5
0
GPA>3.0 GPA<3.0
Smoking Male
Smoking Female
7
2
4Total 15 Smokers
2
Conditional Probability
Table 3.
GPA>3.0
GPA<3.0
Total 90 Nonsmokers
Nonsmoking Male
38
13
Nonsmoking
Female
30
9
51 Males
39 Females
Conditional Probability
Table 5.
Age ≤20
Age > 20
Total 105
Male
51
11
62 Males
Female
33
10
43 Females
Table 6.
Age ≤20
Age > 20
Total 15
Male Smokers
8
3
11 Males Smokers
Female Smokers
2
2
4 Females Smokers
Conditional Probability
Event 1= Male
P(E1)=62/105
Event 2= Female
0.590476
0.409524
P(E2)=43/105
P(E1 or E2)=P(E1)+P(E2)-P(E1 and E2)
.590476+.409524-0=1.0 Probability of Either a Male or Female
Conditional Probability
P(E1 and E2)
4/105=.0380 Probability of Female and Smoker
Event 1= Female
P(E1)=43/105
0.40952
4
Event 2=Smoker
P(E2)=15/105
0.14285
7
P(E1 or E2)=P(E1)+P(E2)-P(E1 and E2)
.409524+.142857-.0380=
0.514381 Probability of Either Female or smoker
Conditional Probability
P(E1 and E2)
11/105=.10476 Probability of Male and Smoker
Event 1= Male
P(E1)=62/105
0.5904
76
Event 2=Smoker
P(E2)=15/105
0.1428
57
P(E1 or E2)=P(E1)+P(E2)-P(E1 and E2)
.590476+.142857-.10476=
0.342859 Probability of Either Male or Smoker
Gender Vs. GPA (Male)
Event 1= Male
P(E1)=62/105
.5905 Probability
Event 2= GPA > 3.0
P(E2)=77/105
.73333 Probability
P(E1 and E2)
45/105=.42857 Probability of Male and GPA > 3.0
Gender Vs. GPA (Female)
Event 1= Female
P(E1)=43/105
0.409524
Event 2= GPA > 3.0
P(E2)=77/105
.73333 Probability
P(E1 and E2)
32/105=.30476 Probability of Female and GPA > 3.0
Smoking Vs. GPA (Male)
Event 1= Male Smoker
11/105=.10476 Probability of Male and Smoker
Event 2= GPA > 3.0
P(E2)=77/105
.73333 Probability
P(E1 and E2)
7/105=.066667 Probability of Male Smoker and GPA > 3.0
Smoking Vs. GPA (Female)
Event 1= Female Smoker
4/105=.0380 Probability of Female and Smoker
Event 2= GPA > 3.0
P(E2)=77/105
.73333 Probability
P(E1 and E2)
2/105=.0190 Probability of Female Smoker and GPA > 3.0
Binomial Formula
n !
P(x)
n= Random Sample Size
p x q n - x
=
x!
(n
-
x )!
x= Number of successes
n-x= Number of Failures
p= probability of a success
0.14285714
q=1-p = Probability of a failure
0.85714286
n!=n(n-1)(n-2)(n-3)…1
0!=1 by definition
30
7.56E-06
Random 30 variable sample
FACTORIAL
P(x)=
30!
4!(30-4)!
(.14285714) power of 4(.85714286) power of 26
4.16E-04
0.0181712
Sampling Error
• Comparing GPA to non-smokers and smokers.
• Using a Cluster Sample technique and a random number generator
Total
Non-smokers
Smokers
Population Mean
3.13
3.16
2.95
Sample Mean
3.137667
3.10
3.08
Error
0.004349
-0.06
0.13
• Population size (105)
• Sample sizes: Total (30), non-smokers (20), and smokers (5)
Margin of Error
• Margin of error in GPA compared to non-smokers and smokers.
Total
Non-Smokers
Smokers
Population Mean
3.13
3.16
2.95
Population S.D.
0.375
0.365
0.396
Sample Mean
3.13
3.10
3.08
Confidence Interval
95%
95%
95%
Margin of Error
0.13
0.15
0.35
Range
3.00 – 3.26
2.95 – 3.25
2.73 – 3.43
• Population size (105)
• Sample sizes : Total (30), non-smokers (20), and smokers (5)
Hypothesis test
non-smokers
• Lower tail t-test
• Null Hypothesis of a 2.00 GPA
• If lower, then reject.
• Level of significance (0.02)
Total
Non-smokers
Data
Null Hypothesis
m=
Level of Significance
Sample Size
Sample Mean
Sample Standard Deviation
Intermediate Calculations
Standard Error of the Mean
Degrees of Freedom
t Test Statistic
Lower-Tail Test
Lower Critical Value
p-Value
Do not reject the null hypothesis
Data
2
0.02
30
3.13
0.417219
0.076173419
29
14.83457105
-2.150325074
1
Null Hypothesis
m=
Level of Significance
Sample Size
Sample Mean
Sample Standard Deviation
Intermediate Calculations
Standard Error of the Mean
Degrees of Freedom
t Test Statistic
Lower-Tail Test
Lower Critical Value
p-Value
Do not reject the null hypothesis
2
0.02
20
3.1
0.357627
0.079967828
19
13.75553174
-2.204701336
1
Hypothesis test
smokers
• Lower tail t-test
• Null Hypothesis of a 2.00 GPA
• If lower, then reject.
• Level of significance (0.02)
Total
Smokers
Data
Null Hypothesis
m=
Level of Significance
Sample Size
Sample Mean
Sample Standard Deviation
Intermediate Calculations
Standard Error of the Mean
Degrees of Freedom
t Test Statistic
Lower-Tail Test
Lower Critical Value
p-Value
Do not reject the null hypothesis
Data
2
0.02
30
3.13
0.417219
0.076173419
29
14.83457105
-2.150325074
1
Null Hypothesis
m=
Level of Significance
Sample Size
Sample Mean
Sample Standard Deviation
Intermediate Calculations
Standard Error of the Mean
Degrees of Freedom
t Test Statistic
Lower-Tail Test
Lower Critical Value
p-Value
Do not reject the null hypothesis
2
0.02
5
3.08
0.334664
0.149666291
4
7.21605376
-2.998527873
0.999022157
Correlation
GPA of non-smokers
4.5
y = 1.0006x
R² = -5.763
4
3.5
3
2.5
Series1
2
Linear (Series1)
1.5
1
0.5
0
0
1
2
3
4
5
Correlation
GPA and smokers
4
y = 0.8429x
R² = -11.43
3.5
3
2.5
Series1
2
Linear (Series1)
1.5
1
0.5
0
0
1
2
3
4
5
Correlation Regression
120
100
y = 2.427x
R² = -0.303
80
Series1
60
Linear (Series1)
40
20
0
0
5
10
15
20
25
30
35
Conclusion
• There is no correlation between smoker and non-smoker
• Based on our data , mean for smokers has a lower GPA
compare to non-smokers
• Although our data revealed a low percentage of smokers
within a 105 person population as a group based on this
result we conclude the percentage of smoking amongst
the campus population is relatively low.
Suggestion
• Make smoker-free
campus.
• Switch the smoking
designated area
- General Lots - (Lots
J, K, L, N, O, X, Y,
and Z ).
• Promote nonsmoking habit by
encouraging students.