5.5.4 Tutorial for Data Transformation

Tutorial-DT

Notes for Starting

• Download the sample project file from here and open it in Origin.

• Start this tutorial with the app Statistical Process Control installed. If you have not installed the app, see Apps for Origin to find and install the app.

Topics for Further Reading: Introduction:Data Transformation Algorithms:Data Transformation

User Story

A house builder has house sold data in the surrounding area. He has found out the distribution of the data does not follow normal distribution using the Identify Data Distribution tool.

He wants to transform the data to make data approximately normal for follow-up analysis.

Steps in Origin

1. Open the sample project file in Origin, go to Folder 3. Nonnormal using the Project Explorer. Activate the workbook House Sold
2. Highlight column B in worksheet. Click the Statistical Process Control icon in the Apps Gallery window.
3. Choose Data Transformation tab, all the data are larger than 0. From the decision tree, we should use Box-Cox method. Click Box-Cox Transform icon to open the dialog
4. In the Input tab of the opened dialog, column B will be selected automatically as Measurement Data. Choose Subgroup Size By to be Constant and set the Subgroup Size Constant to be 1

   

5. Accept all other default settings and click OK button

Interpreting the Results

1. Double click on the embedded graph on report sheet
   • The confidence interval for is [0.11, 0.52], it does not include 1. It means a transformation is appropriate.
   • From the histogram and probability plot of transformed data, we can see the data are approximately normal after the transformation.