Competency

Examine basic descriptive statistics, and demonstrate results using calculated values and statistical charts.

Instructions

Scenario (information repeated for deliverable 01, 03, and 04)

A major client of your company is interested in the salary distributions of jobs in the state of Minnesota that range from $40,000 to $120,000 per year. As a Business Analyst, your boss asks you to research and analyze the salary distributions. You are given a spreadsheet that contains the following information:

• A listing of the jobs by title
• The salary (in dollars) for each job

The client needs the preliminary findings by the end of the day, and your boss asks you to first compute some basic statistics.

Background information on the Data

The data set in the spreadsheet consists of 364 records that you will be analyzing from the Bureau of Labor Statistics. The data set contains a listing of several jobs titles with yearly salaries ranging from approximately $40,000 to $120,000 for the state of Minnesota.

What to Submit

Your boss wants you to submit the spreadsheet with the completed calculations. Your research and analysis should be present within the answers provided on the worksheet.

Work has been completed just a couple errors that need fixed.

Here’s what’s wrong:  I correctly solved almost all the problems and complete and detailed steps are provided to explain how to solve each.  Your explanations demonstrate a mastery of understanding of the statistical concepts and correct terminology is used throughout.

There are two errors early on when you are classifying your variables.  One is in designating the job title variable as discrete, but qualitative variables do not get classified as either discrete or continuous, that is just for quantitative variables.  That alone wouldn’t have been enough to drop your score from a 4 to a 3, but you do have the incorrect level of measure for the salary variable.  The correct level of measure will reflect the fact that salaries have a natural zero starting point (it doesn’t matter if 0 is not in the data set).

All of your explanations for the different measures of center and measures of variation are great, thorough and accurate.

All of your calculations are correct, but there are some that could be done much more easily.  Excel has built in formulas for variance, standard deviation, and mode (even for multiple modes).  Using the programmed Excel formulas is not only a big time saver, but it also ensures you avoid any rounding errors and greatly reduces the chance of user error.