Cory Butts
Statistical Report
Professor Klaus
December 4, 2014
Introduction
The purpose of this paper is to work with commonly used terms is statistics and applying
them to real life situations. The importance of this is the understanding of figuring out the
diastolic pressures between males and females. This understanding will be figured by computing
the center, measures of variation, five number summaries, and boxplots. The results will be
obtained through hypothesis testing of the male and female diastolic blood pressures. Below,
results can be found.
Methods
The first step of the experiment was to transfer all of the data into an excel spreadsheet.
The data was obtained through The Centers for Disease Control and Prevention. Second, the
descriptive statistics were calculated through excel for the male diastolic blood pressures and the
female diastolic blood pressures. Third, histograms of the frequency distribution were made for
each variable. These numbers were used to create a boxplot which includes the minimum value,
maximum value, and each of the three quartiles. The box plot was created using the Microsoft
Word shapes feature. Next, the confidence intervals were found and compared to the significance
level through hypothesis testing. The hypothesis testing was done through excel and the
calculator.
Results
The center of the data for the male includes the mean of 73.25, median of 75, and mode
of 81. The range went from 44-87, with a standard deviation of 9.13 and a sample variance of
83.41. Q1 is found to be 66.5 and Q3 is found to be 81. The IQR resulted in 14.5. Because the
lower limit is 44.75 and the upper limit is 102.75, it was found that 44 is an outlier from the data
set. With that said, the information above determined that this sample did not come from a
normal population distribution because there is an outlier and the box plot shows that it is heavily
skewed. Also, the mean and standard deviation do not reflect a normal curve because the curve
is not necessarily symmetric around its peak.
Boxplot for Diastolic Male Blood Pressures
40
50
60
70
80
90
100
Frequency
Frequency Distributions for Male Diastolic Blood
Pressure
16
14
12
10
8
6
4
2
0
40-49
51-59
60-69
70-79
80-89
90-100
Diastolic Male (mmHg)
The 95% confidence interval for the mean of all males was calculated to be 2.92. The
95% confidence interval for the mean of all females was calculated to be 3.72. The 95%
confidence interval for the difference between the mean of all males and the mean of all the
females was found to be 4.56. There is a difference between the two means based on the
calculations computed. For a hypothesis test with a significance level of 0.5, Ho=0, and H1≠0.
This makes the equation two tailed. The test statistic resulted in 2.573 and the p-value is .014.
The p-value is then compared to the significance level (.014≤.05). Since this is true then Ho is
rejected. The conclusion is that the diastolic blood pressure is higher in males. The results from
the hypothesis test and the confidence level differed by the hypothesis value being lower than the
confidence level.
Discussion
The main difficulties was taking the information and finding the correct results while
using the correct methods. There are many numbers to be evaluated and an answer can be wrong
by just entering the wrong number. It is very important to pay attention to detail and double
check the methods and steps throughout the research. The results show that men and women
both contain high blood pressures but that the men are more vulnerable to having a high blood
pressure. With that said, it was not surprising that men have higher blood pressure because
throughout history, men have more issues than women when it comes to high blood pressure.
The main thing that people can take from this study is that anyone can get high blood pressure
and that men need to be more careful and aware that they have a higher chance for high blood
pressure. These results can allow other doctors and medical personal to pay more attention to
men’s blood pressure and look more closely as to how they can stop this terrible disease. With
that said, there needs to be more studies on men’s blood pressures.
Conclusion
Overall, it is important to know that blood pressure is a very important heath concern that
both men and women need to take seriously. With that said, the research showed that both men
and women are victims of high blood pressure but men have a higher blood pressure. Also, the
graphs such as the histograms excel spreadsheets, and box plots show all the necessary research
that is needed on the men’s and women’s blood pressures. All in all, the research shows that
men are more at risk when it comes to blood pressure
Bibliography Sources
Centers for Disease Control and Prevention. (2014). National Health and Nutrition Examination
Survey. Retrieved from http://www.cdc.gov/nchs/nhanes.htm
Appendix A
DIAS Male
Mean
Standard Error
Median
Mode
Standard Deviation
Sample Variance
Kurtosis
Skewness
Range
Minimum
Maximum
Sum
Count
Confidence Level
(95.0%)
q1
q3
IQR
Lower
Upper
Outliers
73.225
1.444036144
75
81
9.132886476
83.40961538
1.373590924
1.006718312
43
44
87
2929
40
2.920838796
66.5
81
14.5
44.75
102.75
44
DIAS FEMALE
Mean
Standard Error
Median
Mode
Standard Deviation
Sample Variance
Kurtosis
Skewness
Range
Minimum
Maximum
Sum
Count
Confidence Level(95.0%)
67.425
1.838298928
66
61
11.62642327
135.1737179
1.202718315
0.366948472
61
41
102
2697
40
3.71831055
61
Difference Male and Female
Mean
Standard Error
Median
Mode
Standard Deviation
Sample Variance
Kurtosis
Skewness
Range
Minimum
Maximum
Sum
Count
Confidence Level(95.0%)
5.8
2.253828651
6
1
14.25446399
203.1897436
0.009255537
-0.074746317
64
-27
37
232
40
4.558798748
t-Test: Paired Two Sample for Means
Mean
Variance
Observations
Pearson Correlation
Hypothesized Mean
Difference
df
t Stat
P(T<=t) one-tail
t Critical one-tail
P(T<=t) two-tail
t Critical two-tail
Variable
Variable 1
2
73.225
67.425
83.40961538 135.1737
40
40
0.072486265
0
39
2.573398824
0.006993637
1.684875122
0.013987273
2.02269092
Frequency
40-49
51-59
1
2
60-69
70-79
80-89
90-100
11
14
11
0
Frequency
Frequency Distributions for Male Diastolic Blood
Pressure
16
14
12
10
8
6
4
2
0
40-49
51-59
60-69
70-79
Diastolic Male (mmHg)
80-89
90-100
Appendix B
I have learned a lot about statistics after completing this project. The main thing that I
learned was how to combine Excel and statistical information to find results. I think being able
to use Excel is a great tool that I can use when I try to find jobs in the near future. Also, I
learned how to find a difference in means using excel and by using the calculator and applying
that to an Excel spreadsheet to find results. Also, I learned how to make a histogram which has
helped me become better at using the Excel program. All in all, I learned how to do a statistical
report and apply all the things I learned in my statistics class and apply it to real life situations,
such as men and women blood pressures.