Grouped Correlation The Grouped Correlation tab is shown below: This plot shows computed correlations and scatterplot matrices for expression measurements across groups of arrays. One array is generated for each group; three groups are represented in the figure above. Most of the arrays fall into an elliptical space along the diagonal axis. In general, a tighter ellipse means a higher correlation, and more circular ellipses indicate increased noise. The spots outside the ellipses might be outlier genes of interest in terms of quality control or an inconsistent signal across replicates.