Use a 3D scatterplot to see how a response variable relates to two predictor variables. A 3D scatterplot is a three-dimensional graph that is useful for investigating desirable response values and operating conditions.
A 3D scatterplot contains the following elements:
Predictor values on the x- and y-axes.
Response values on the z-axis.
Using the 3D scatterplot, you can view only the actual data values, with no interpolation between the data points such as in a contour plot or 3D surface plot. Use the plot to explore the direction, strength, and linearity of the relationship between the three variables:
Data points that tend to rise together suggest a positive correlation.
Data points that tend to rise as other data points tend to decline suggests a negative correlation.
Outliers fall far from the main group of data points.
Adding project lines helps you visualize each point's position in three-dimensional space. For more information, go to Adding project lines to a graph. Rotate the graph to view the plot from different angles and explore possible relationships in the data. For more information, go to Viewing a 3D scatterplot.