This chapter contains the following main sections:

• Problem Description and Objectives
• Data Description
• Loading the Data into R
• Data Visualization and Summarization
• Unknown Values
  • Removing the Observations with Unknown Values
  • Filling in the Unknowns with the Most Frequent Values
  • Filling in the Unknown Values by Exploring Correlations
  • Filling in the Unknown Values by Exploring Similarities between Cases
• Obtaining Prediction Models
  • Multiple Linear Regression
  • Regression Trees
• Model Evaluation and Selection
• Predictions for the Seven Algae
• Summary