The best type of graph for showing the relationship between two quantitative variables is a scatter plot.
- A scatter plot displays individual data points where one quantitative variable is plotted on the x-axis and the other on the y-axis, allowing visualization of how the two variables relate to each other
- It can reveal patterns such as linear or nonlinear relationships, strength of association, and potential outliers
- Scatter plots can be enhanced by adding color, size, or shape to represent additional variables, or by connecting points in temporal order to form connected scatter plots if time is involved
- Alternatives like heatmaps can be used when there are many data points causing overplotting, but scatter plots remain the standard and most informative choice for two quantitative variables
In summary, a scatter plot is the classic and most effective graph for exploring and illustrating the relationship between two quantitative variables.
