Scatterplots are needed to display relationships

The relationship between two variables cannot be determined from examination of the two variables in isolation.

The diagram below shows the univariate distributions of two variables X and Y as jittered dot plots against the axes.

Can you guess the relationship between X and Y from the two jittered dot plots that are shown against the axes?

Use the pop-up menu to display various scatterplots that are consistent with the univariate jittered dot plots. We will see later that these different scatterplots imply very different types of relationship between the variables. It is therefore important to use a scatterplot to determine the type of relationship.