1. Examining Relationships
Chapter 3

2. Scatterplots
A scatterplot shows the relationship between two quantitative variables measured on the same individuals.
The explanatory variable is graphed on the x-axis and the response variable is graphed on the y-axis.
Scatterplots reveal the strength, type, and direction.

3. Patterns (STD’s)
Strength: determined by how close the points in the scatterplot are linear (“Strong, moderate, or weak”)
Type: linear is preferred, but curves and clusters are significant (“linear or nonlinear”)
Direction: variables are either positively associated or negatively associated (“positive or negative”)