Comparisons can be defined during the experiment design process and after the experiment has finished processing.
When setting up comparisons on ROSALIND, you can select a category from the left column to explore your samples and then drag and drop individual samples or sample attributes into each group box. When using the attributes category, ROSALIND looks for samples that satisfy all of the attribute requirements that you drag and drop into each group. Therefore, you can add multiple attributes to each group box to narrow down and define the groups or specific samples you want to compare. The number on the bottom of each group box shows the total number of samples that qualify. You can view and deselect specific samples by clicking on the EDIT button in the bottom right corner and then clicking on the triangle to see a check list. For best statistical practices, it is recommended to include a minimum of 3 samples on each side of the comparison.
An optional covariate selection is available in Gene Expression experiments to correct for confounding variables. ROSALIND intelligently determines which experiment attributes may be valid covariates, reducing complexity. Please click here for more information on Covariate Correction in ROSALIND.