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• In the Sample Information panel, specify the column labels (Labels 1-4) as Type, Tissue, Subject, and Gender, set each as categorical, and set the other columns as skip (Figure 1). Select OK
  
  

• A dialog window asking if you would like to save the spreadsheet with the new sample attribute will appear. Select Yes
• Make column 5. (Subject) random by right-clicking on the column header and selecting Properties from the pop-up menu (Figure 2). 
  
  

• Select the Random Effect check box from the Properties dialog (Figure 3) then select OK. 
  
  

The column 5. (Subject) will now be colored red, indicating that it is a random effect. 

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