Lesson 5: Residual Analysis and R-Squared

January 30, 2016

Previous | Next

Mon, Feb 1

Review:

• Simple Regression
• Problem solutions – use odd number textbook problems to practice
• Exam 1 on Wed, Feb 17

Presentation:

• Residual Analysis
  • Individual Residuals
  • Residual Plot(s)
  • Residual Sum of Squares (SSE) = ∑(y – y-hat)²
  • Total Sum of Squares (SSyy) = ∑y² – (∑y)²/n
  • Coefficient of Determination
    • r-squared = 1 – SSE/SSyy
    • Relationship to Pearson Correlation Coefficient

Activity:

• Use data from Problems 12.2 (p. 474) and 12.6 (p. 481)
  • Calculate and plot residuals
  • Calculate SSE
  • Calculate r-squared
  • Scatter Plot of Actual (y) vs Predicted (y-hat)

Assignment:

• Repeat the Activity (12.2 & 12.6) in Sheets
• Use your 10 countries GDP and Fertility data to complete the following in Sheets
  • Calculate and plot residuals
  • Calculate r-squared
  • Scatter Plot of Actual (y) vs Predicted (y-hat)