Scattergraphs

A scattergraph, also known as a scatter plot or scatter diagram, is a type of mathematical diagram that uses Cartesian coordinates to display values for typically two variables for a set of data. The data is displayed as a collection of points, each having the value of one variable determining the position on the horizontal axis and the value of the other variable determining the position on the vertical axis. Scattergraphs are useful for observing relationships between variables.

The primary purpose of a scattergraph is to identify potential correlations between two quantitative variables. If the points on the graph tend to cluster around a line or curve, it suggests a relationship exists. A relationship where as one variable increases, the other also tends to increase is called a positive correlation. Conversely, if as one variable increases, the other tends to decrease, it is a negative correlation. If there is no discernible pattern, the variables may be uncorrelated.

Scattergraphs are widely used in various fields including statistics, science, engineering, and finance. They can help in visualising trends, identifying outliers, and providing a basis for regression analysis, which aims to model the relationship between variables. The strength and direction of the relationship can be inferred from the visual spread and orientation of the plotted points.