What do scatter diagrams represent?

Scatter diagrams are graphical representations used to display the relationship between two quantitative variables. They plot individual data points on a two-dimensional graph, with one variable on the x-axis (independent variable) and the other on the y-axis (dependent variable). This allows for visual analysis of the correlation or relationship between the two variables. By observing the pattern of the points, one can determine if a positive, negative, or no correlation exists.

Choosing the correct understanding of scatter diagrams as representations of independent and dependent variables enables analysts to make predictions, identify trends, and assess the strength and direction of relationships within data sets. This capability is particularly valuable in mass appraising, where understanding the influence of one factor (like square footage of a property) on another (like property value) is essential for accurate assessments.

In contrast, the other options represent different contexts or concepts and do not accurately reflect the primary use of scatter diagrams. Time and quantity, income and expenditure, and supply and demand can all involve relationships between variables, but these are not the specific pairings represented by scatter diagrams within a statistical context.