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Presenting data analysis results to the business people is one of the hardest tasks. One has to avoid technical terms and explain math concepts in simple and clear language. Recently I faced this problem again having to present decision tree model to my director.

The best idea I came up with was to print the decision tree on A2 size paper. The idea worked well because the print attracted a lot of attention and provoked a long discussion. This article is devoted to the tricks to improve the decision tree schema that is created by the SAS Enterprise Miner Decision Tree node.

Printing

One can print decision tree from the Results window but SAS automatically scales the image to fit it on one page. If you don’t have a large format printer available all the legends on your print will be too small to read.

I didn’t have large format printer either. I copied the decision tree image (open Results windows and go to Edit → Copy), pasted it into the Paint editor and saved it as a file. Then I inserted the file into Excel that allows 1:1 scale printing spreading the image across multiple pages.

But even Excel leaves empty margins on a list. Having printed the image I cut off the margins with a paper knife and a metal ruler.

Title and footnote

You can add title and footnote either in Paint or SAS. In SAS open the Results windows, right click on the tree image and choose Graph properties → Title/Footnote. For instance, you can add the following:

• Title: Application Scoring v1.0
• Subtitle: on clients’ data collected January 1 - June 1, 2009.
• Footnote: “1” – client responded in less than 3 months, “0” – did not.

I also recommend changing background color to white in the Graph menu. That will save some printer ink and make your image brighter.

Labels

If your input data set doesn’t have labels you will see variables names on the decision tree. They are often uninformative. If the labels are present the names are replaced with labels automatically. You can add or replace labels the following way:

• Add Transform Variables node to the diagram.
• Place it right after the Data Source node.
• Click SAS Code button on the left and print the following code in the window:

label <variable name> = “<description>”;

Label is the Base SAS operator that adds descriptions (labels) to the data set variables. After running the entire diagram path you will see variables labels on the decision tree image.