What is the intention?
• I intend on hopefully finding a correlation
between a high school student’s gender and
their GPA. The intended population is
Kenwood Academy High School students in all
grades. This seems like a great sample
because it was really concise and small.
Sample. Confidence. Revision.
• I randomly asked 57 people, 29 females and 28 males
for their GPA’s. I designed this experiment because I
felt that there was some type of correlation between
the gender and a passing GPA.
• I believe that my experiment was strong and I am
confident in my sample, because it was simple to get
the data, however, it is weak in knowing that my all my
data was circumstantial and resulted in some
uncertainty.
• I did encounter a problem with trying to keep all of the
conditions and had to change my approach twice ,
but it turned out good .
Biases  ?!? &
Lurking Variables !!!..
Ohhhh! Noooo!
• Okay you may ask, what sort of biases I encountered,
well, quite a few actually.
• One, the response bias, in that everyone asked was
not sure of their GPA’s and that created inaccuracy.
• Secondly, I also encountered that fact that the
sample of students asked were mostly students that I
felt comfortable asking thusly it made the project
biased in that way also.
• Last, but not least the dreaded lurking variable,
nope…did not see it… lets move on, okay.
Pose a Question?
…Really, I thought this was a research paper!
Is there an association
between a passing GPA
and gender?
Procedure, Insight, Preliminaries!
If you do not know
your GPA right now,
can you give me an
educated guess?
Can you give me
your GPA?
A
(4.0+)
B
(3.9-3.0)
C
(2.9-2.0)
Female
8
13
8
Male
6
10
12
GPA vs. Gender
…hmmm, girls seem smarter… but
where is the association?
Female and Male Statistics in a
back-to-back Box Plot
14
12
10
8
6
4
2
0
Female
Male
There are no
ends, or arms to
these boxes,
well, some of
the values were
repeated more
than once thus
creating these
boxes.
Five Number Summary!
Mean
∑x
σ
n
Min
Q1
Med
Q3
Max
Female
9.667 29
2.35
3
8
8
8
13
13
Male
7.33
2.494
3
6
10
12
12
12
28
Commentary on Explanatory Data
• Shape: there is almost no shape in the box plots but in the
bar graph, there is some correlation and similarities apparent
in the graph and without doubt, the graph shows different
patterns when you compare counts and if you were to
consider how each sector looks another thing you can see is
how in the second graph on the bar graph each category of
data is somehow increasing at a decreasing rate .
• Outliers: There were no observed outliers.
• Center: The center for the females and males shared its value
under another statistic.
• Spread: As in the box plot, there is not much spread between
the other values, thus a box without a median or “arms”.
Null and Alternate Hypothesis and
other important info!
Ho : μ (gender ) = μ (GPA )
Ho: There is an association between gender and a
passing GPA among KA High School students.
Ha : μ (gender ) ≠μ (GPA )
Ha: There is not an association between gender and
a passing GPA among KA High School students.
• Significance Level: 5%
• Sample size: 57
Chi Squared Test
Tests for independence and relationship
among two things.
I chose this test because I thought that it
would be most effective in comparing a
passing GPA with gender a non-quantitative
value.
Check conditions:
SRS: There is a SRS of 57 out of a pop of about
1800 students, including the AC.
Each Expected Value: ≥ 5
So, it looks like we can proceed to the ChiSquared Test for Independence!
Calculations!
(8-7.128)2/
(13-11.702)2/
(8-10.175)2/
7.128 +
11.702 +
10.175 +
(6-6.8772)2/
(10-11.298)2/
(12-9.8246)2/
6.8772 +
11.298 +
9.8246
Fact Checking! OK! & It’s time 2
Reject or Fail to Reject!
 I got the P value, DF, and X2 statistic from the TI-84 Plus.
 Based upon my P value, I will decide to fail to reject the
Ho hypothesis!
 Is there an association between gender and a passing
GPA? Well, yes there is an association between gender
and a passing GPA.
Ok, guys we’ve reached the end!
Okay! Time to reflect!
• I believe that at the end of the day, my question of whether
or not there is an association between GPA and Gender, has
been answered. But there were plenty of times where the
data failed to satisfy some of the conditions and it also
affected the outcome of the project, only after the omission
of the data relative to the inconsistent results, was the data
acceptable. I asked questions about GPA and recorded their
genders.
• The main weakness of the project was the fact that all
categories of GPA’s were not included which could have
biased the project a little more than expected. Otherwise
everything stood valid.
Bye!