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Start by choosing a factor or interaction from the Factor drop-down list. The subgroups of the factor or interaction will be displayed in the left panel; click to select a subgroup name and move it to one of the panels on the right. The fold change calculation on the comparison will use the group in the top panel as numerator, and the group in the bottom panel as the denominator. Click on Add comparison button to add one comparison to the comparisons table. Note that multiple comparisons can be added to the specified model.

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