Lesson 7: Relationships Between Categorical Variables

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  • Complete the 'Poll Monday' and 'Thinking Tuesday' Activities for Lesson 7.
  • Read Chapter 12 in the text.
  • Work through the Lesson 7 online notes that follow.
  • Complete the Practice Questions and Lesson 7 Assignment.

Learning Objectives

Chapter 12

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

  • Use a table of cross-classified data to find summaries that answer questions of interest about data.  This includes the ability to:
    • Distinguish between and interpret: percentages, probabilities, conditional percentages, and conditional probabilities
    • Distinguish between and interpret: risk, relative risk, and increased risk.
    • Distinguish between and interpret: odds and odds ratio
  • Understand that an observed association between two variables can be misleading or even reverse direction when there is another variable that interacts strongly with both variables (Simpson's Paradox)

Terms to Know

click on the terms to learn more

From Chapter 12

  • contingency table
  • 2 × 2 (contingency) table
  • sample percent/proportion
  • conditional percent/proportion
  • population probability and conditional probability
  • odds
  • odds ratio
  • risk
  • relative risk
  • increased risk