Understanding the relationship between two quantitative variables is often needed in epidemiology and biostatistics. For example, a researcher might need to know the relationship between birth and death rates. Think of an example that's interesting to you that concerns the relationship between two quantitative variables.
Describe the issue and clearly identify the observational units and the two quantitative variables. How could you illustrate this with a scatterplot?
Finally, if a scatterplot revealed a strong association, is this sufficient statistical evidence to show cause and effect? Explain your response