Lesson 3: Getting the Big Picture and Summaries

Lesson Overview Section

The goal of this lesson is to pull together what we have learned about appropriate ways to gather data and how the design of a study affects the way we interpret its results. Then, when the study is completed and we have the resulting data in hand, we must learn to summarize the salient features of those data through graphs and numerical summaries. The methods we will focus on are appropriate for all measurement variables regardless of whether the variable is discrete or continuous.

Objectives

After successfully completing this lesson, you should be able to:

  • Effectively critique reports about scientific studies and recognize the statistical issues involved.
  • Interpret any of the four graphs used with measurement data.
  • Interpret measures of center and measures of spread.
  • Determine when sensitive statistics or resistant statistics should be used to describe a data set.
  • Interpret a five-number summary.