Descriptive Statistics and Interpretation Example QNT/561 Version 8 7 University of Phoenix Material Descriptive Statistics and Interpretation Example Interpretation Phrases Central Tendency: Mean = average of a set of data Median = half or equal number of data is above and half or equal number of data is below. It is a midpoint in an ordered (sorted) set of data, a physical location Mode = most frequent value in a set of data Dispersion: Standard deviation = variation Interquartile range (IQR) = the middle 50% of the data Range = the difference between the largest and smallest value of the data Confidence Interval: (data must be normal) There is 95% confidence that the population average is between _____ and ____ units. Normal or significantly skewed data: MegaStat: Descriptive statistics Normal curve goodness of fit p-value Normal, p-value > .05 Significantly Skewed, p-value < .05 Histogram: Eyeball the histogram. Normal data will have a symmetrical or slightly skewed shape. Significantly Skewed shape will have extreme skewness Use phrase combinations: Normally distributed: Mean and Standard Deviation, Not normally distributed: Median and IQR Descriptive Statistics Body Weight (Lbs.) Central Tendency: Mean = 149 Lbs. Dispersion: Standard deviation = 30 Lbs. Count: 100 Min/Max: 99 pounds and 234 Lbs. Confidence Interval: 144 to 155 Lbs. See the histogram in Appendix A, and descriptive statistics in Appendix B. Age Distribution is not normally distributed Central Tendency: Median = 36 years Dispersion: Interquartile Range = 20.5 years / 2 = ± 10 years Count: 100 Min/Max: 18 years and 74 years Confidence Interval: Not applicable (data is not normally distributed) See the histogram in Appendix A, and descriptive statistics in Appendix B. A scatter plot is in Appendix C. Education Level Thirteen percent of the subjects have no high school degree while 44% have high school degree. Forty three percent have a college or college graduate degree. See the bar chart in Appendix D. Descriptive Statistics Interpretation Interpretation Body Weight One hundred subjects were randomly selected. Their body weight was observed between 99 and 234 pounds. Their average weight was 149 pounds, with a variation of plus or minus 30 pounds. One half or more were above 149 pounds. There is 95% confidence that the population body weight average is between 144 and 155 pounds. Age The data was significantly skewed. One hundred subjects were randomly selected. Their ages were between 18 and 74 years, with a variation of plus or minus 10 years. One half or more subjects were 36 years of age or older. The middle half of the subjects’ ages fell between 27 and 47 years. The most frequent age was 36 years. APPENDIX A Body Weight and Age Histograms APPENDIX B Descriptive Statistics Body Weight and Age APPENDIX C Scatterplot Body Age versus Weight APPENDIX D Bar Chart Education Level Copyright © 2015 by University of Ph.

1. Descriptive Statistics and Interpretation Example
QNT/561 Version 8
7
University of Phoenix Material
Descriptive Statistics and Interpretation Example
Interpretation Phrases
Central Tendency:
Mean = average of a set of data
Median = half or equal number of data is above and half or
equal number of data is below. It is a midpoint in an ordered
(sorted) set of data, a physical location
Mode = most frequent value in a set of data
Dispersion:
Standard deviation = variation
Interquartile range (IQR) = the middle 50% of the data
Range = the difference between the largest and smallest value
of the data
Confidence Interval: (data must be normal)
There is 95% confidence that the population average is between
_____ and ____ units.
Normal or significantly skewed data:
MegaStat: Descriptive statistics Normal curve goodness of fit p-

2. value
Normal, p-value > .05
Significantly Skewed, p-value < .05
Histogram: Eyeball the histogram.
Normal data will have a symmetrical or slightly skewed shape.
Significantly Skewed shape will have extreme skewness
Use phrase combinations: Normally distributed: Mean and
Standard Deviation, Not normally distributed: Median and IQR
Descriptive Statistics
Body Weight (Lbs.)
Central Tendency:
Mean = 149 Lbs.
Dispersion:
Standard deviation = 30 Lbs.
Count:
100
Min/Max:
99 pounds and 234 Lbs.
Confidence Interval:
144 to 155 Lbs.
See the histogram in Appendix A, and descriptive statistics in
Appendix B.
Age
Distribution is not normally distributed
Central Tendency:
Median = 36 years
Dispersion:

3. Interquartile Range = 20.5 years / 2 = ± 10 years
Count:
100
Min/Max:
18 years and 74 years
Confidence Interval:
Not applicable (data is not normally distributed)
See the histogram in Appendix A, and descriptive statistics in
Appendix B. A scatter plot is in Appendix C.
Education Level
Thirteen percent of the subjects have no high school degree
while 44% have high school degree. Forty three percent have a
college or college graduate degree. See the bar chart in
Appendix D.
Descriptive Statistics Interpretation
Interpretation
Body Weight
One hundred subjects were randomly selected. Their body
weight was observed between 99 and 234 pounds. Their average
weight was 149 pounds, with a variation of plus or minus 30
pounds. One half or more were above 149 pounds. There is 95%
confidence that the population body weight average is between
144 and 155 pounds.
Age
The data was significantly skewed. One hundred subjects were
randomly selected. Their ages were between 18 and 74 years,
with a variation of plus or minus 10 years. One half or more

4. subjects were 36 years of age or older. The middle half of the
subjects’ ages fell between 27 and 47 years. The most frequent
age was 36 years.
APPENDIX A
Body Weight and Age Histograms
APPENDIX B
Descriptive Statistics Body Weight and Age
APPENDIX C
Scatterplot Body Age versus Weight
APPENDIX D
Bar Chart Education Level
Copyright © 2015 by University of Phoenix. All rights reserved.
SHORT TITLE OF PAPER
1
Running head: DESCRIPTIVE STATISTICS
1Descriptive Statistics
Name
QNT/561
Date

5. Instructor’s Name
Descriptive Statistics
Determine the appropriate descriptive statistics.
Note: If the data was normally distributed, use the mean and
standard deviation. If the data was skewed significantly, use the
median and interquartile range.
Numeric Variable Name1
Distribution: State if not normally distributed
Central Tendency:
Dispersion:
Number:
Min/Max:
Confidence Interval: (if distribution is normal)
Numeric Variable Name2 (if applicable)
Distribution: State if not normally distributed
Central Tendency:
Dispersion:
Number:
Min/Max:
Confidence Interval: (if distribution is normal)
Attribute Variable Name (if applicable)
Create a bar chart. Describe the proportions.
Descriptive Statistics Interpretation
Numeric Variable Name1

6. Describe the variable in laymen terms.
Numeric Variable Name2 (if applicable)
Describe the variable in laymen terms.
Appendix A
Raw data used in the analysis
Fit data to one page.
Appendix B
Charts and Tables
This part of the paper will include items that are then cited in
the body of the paper. Usually, large items are placed here not
to distract from reading the paper.
Appendix C
Descriptive Statistics
This part of the paper will include descriptive statistics.