A mesh is a grid of regularly spaced x- and y-values on which a 3D surface, 3D wireframe, or contour plot is based. Minitab calculates response (z) values at the x-y intersections of the mesh. The mesh is not displayed on a graph. The following graphs illustrate what the mesh might look like.
If the x- and y-values on a plot are not evenly spaced, Minitab interpolates (estimates) the z-values at the intersections of a regular 15 by 15 mesh with the same x- and y-ranges as your data. You can change the interpolation method that Minitab uses. If you are unsure of which method to use, you may want to try both and pick the one that works best for your data. For more information, go to Working with mesh on contour plots and 3D graphs.
To edit the method when you create a graph, click Surface Options or Contour Options, and then select the options on the Method tab. To edit the surface on an existing graph, double-click the surface, and click the Method tab.
In Distance power, enter a number greater than 0 and less than or equal to 12 to indicate the amount of local variation smoothing. The closer to 0, the closer the fits are to the overall mean. The farther from 0, the more weight is placed on local variation.
Select Standardize x- and y-data to standardize the x- and y-data if the data are measured on different scales. (The graph scale does not change.)
In Boundary z-value, enter a z-value to use at the boundaries (corners and edges) of the plot. By default, Minitab uses the minimum z-value.
When x-y data do not form a regular grid, the mesh resolution could have a large effect on the surface plot. If your data were sampled such that your x-y points are close to a regular grid, you might enhance the fit by specifying a mesh similar to that of your data.
Using a mesh with more and smaller intervals than exist between data points may seem to add more resolution to the graph, but the detail is probably only background noise.