Here is sample data showing the weight of coffee beans in bags labeled 5 pounds. The data is in pounds.
1) Compute the mean.
Compute the median.
Compute the mode.
2) Compute the first quartile
Compute the third quartile.
Compute the interquartile range.
3) Find the largest number.
Find the smallest number.
What is the range?
4) What is the difference between the Excel functions, STDEV.P and STDEV.S? (Hint: Use the Excel help files.)
5) What is the variance?
What is the standard deviation?
6) Explain why the standard deviation is a better measure to use than the variance.
7) What is the Coefficient of Variation, or the CV?
When is the Coefficient of Variation especially useful?
Give an example of when you will use Coefficient of Variation in real life. This can be from your work, from the popular press, or from a statistics website.
Copy all of the data into a column, use Column M and go from cell M1:M180.
8) Use the Data Analysis tool on the numbers just copied to find the Descriptive Statistics.
Click on Data Analysis and Choose Descriptive Statistics.
Click on the Summary Statistics box.
Highlight the mean, median, mode, Standard deviation, Range, Minimum, and Maximum.
Notice that the Data Analysis tool gives you all of the info needed for this problem except for the quartiles, variance and CV.
Compare your answers in the previous sections with what you got here. If there is a difference, you probably made a mistake, go back and check your work.
For questions 9 and 10, you are a consultant who is brought in and given these numbers and asked to generate a report to management. What would your recommendation be?
These two parts are your chance to show your understanding of the material.
To do a good job (and justify your consultant fees :)) I would expect at least 1-2 paragraphs on each.
9) Interpret the measures of central tendency within the context of this problem.
Should the company producing the coffee be concerned about the central tendency?
10) Interpret the measures of variation within the context of this problem.
Should the company producing the coffee be concerned about variation?
All formulas, computations, results and explanations are in the Excel file.