Figure 2

Example of a spot with contamination. The filtering procedure removes aberrant pixels (dots with the red contours), improving the Cy5/Cy3 ratio estimation and increasing the coefficient of determination of the linear regression plot. Before filtering (red line): CD = 0.86; linear regression ratio is 1.41; segmentation ratio is 0.712. After filtering (black line): CD = 0.91; linear regression ratio is 0.275; segmentation ratio is 0.273. However, larger amounts of aberrant pixels may result in a less reliable estimation.