Example of a 3D scatterplot
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Your company manufactures frozen foods and you need to determine the optimal time and temperature for reheating a new frozen entree. You reheat samples at a number of different times and temperatures, then have trained judges rate each for overall quality on a scale of 0 (not enjoyable) - 10 (most enjoyable). Create a 3D scatterplot with project lines to illustrate the average quality scores.

1    Open the worksheet REHEAT.MTW.

2    Choose Graph > 3D Scatterplot.

3    Choose Simple, then click OK.

4    In Z variable, enter Quality. In Y variable, enter Time. In X variable, enter Temp.

5    Click Data View.

6    Under Data Display, check Project lines. Click OK in each dialog box.

Graph window output

Interpreting the results

Reheating at the shorter time intervals results in under-cooked product and low quality scores. However, reheating at the longest intervals combined with the highest temperatures also results in low scores because the food becomes over-cooked. The optimal settings appear to be between 400° and 450° and between about 30 and 36 minutes.

Adding the project lines helps you visualize each point's position in three-dimensional space. Rotating the graph and viewing it from different angles can also help.

Additional examples that help visualize these data include:

·    Scatterplot with connect line

·    Scatterplot with connect lines and groups

·    3D surface plot

·    3D wireframe plot

·    Contour plot