Tutorial for Identify Data Distribution
Contents
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.
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Topics for Further Reading: |
User Story
A house builder has house sold data in the surrounding area. He want to find out a best fit distribution of the data for follow-up analysis.
Identify Data Distribution
- Open the sample project file in Origin, go to Folder 3. Nonnormal using the Project Explorer. Activate the workbook House Sold
- Highlight column B in worksheet. Click the Statistical Process Control icon
in the Apps Gallery window. - Choose Identify Data Distribution tab, click Identify Data Distribution icon to open the dialog
- 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
- In the Input tab, keep Number of Distributions and Transformations to be All.
- Click OK button. The report sheet will be created
Interpreting the Results
We can compare and select a fitting model based on the following results
Following distributions are good fit for the data. Their P value are larger than 0.05 in the Goodness of Fit Test table. And the points on the probability plot follow a straight line within the confidence bounds.
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- Johnson Transformation (0.369)
- Gamma (0.184)
- Largest Extreme Value (0.104)
- 3-Parameter Weibull (0.1)
- Lognormal (0.074)
Probability (P-P) Plot
The closer all the scatter points are to the reference line, the better the distribution is for the dataset.
Goodness of Fit Test table
