CHAPTER 2

Descriptive Statistics I

ELEMENTARY DATA PRESENTATION AND DESCRIPTION

LEARNING OBJECTIVES

After completing the chapter, you should be able to

  1. Compute and interpret the three main measures of central tendency.
  2. Compute and interpret the four main measures of dispersion.
  3. Summarize data in a frequency distribution.
  4. Summarize data in a relative frequency distribution.
  5. Build and interpret a cumulative frequency distribution.
  6. Analyze grouped data and show that data in a histogram.

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EVERYDAY STATISTICS

Not Many Average Lawyers

Thinking of becoming a lawyer? If salary matters, a quick search of the Internet reveals a pretty promising picture. According to one recent report, the average starting salary for new lawyers is $78,653. Not too bad for your first job out of grad school!

But could most new lawyers expect to earn anything close to this average figure? Before you rush to send out those law school applications, it might pay to take a closer look at another summary measure that was reported for the lawyer salary data. The median salary for new lawyers was $60,000. This means that at least half of the new lawyers surveyed earned $60,000 or less. That's nearly $20,000 less than the average! What's happening here? Clearly a relatively few large salaries are pulling up the overall average salary figure, producing an average that gives an overly bright picture of things.

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