Simple linear regression is a way of evaluating the relationship between two continuous variables. One variable is regarded as the predictor variable, explanatory variable, or independent variable \((x)\). The other variable is regarded as the response variable, outcome variable, or dependent variable \((y)\).
For example, we might we interested in investigating the (linear?) relationship between:
- heights and weights
- high school grade point averages and college grade point averages
- speed and gas mileage
- outdoor temperature and evaporation rate
- the Dow Jones industrial average and the consumer confidence index