Examples of scattergrams for repeated hybridization data, normalized by means of the three-parameter lognormal distribution model. The scattergrams are of two hybridization experiments with the same control probe, thus demonstrating the technical reproducibility of the experiments. Red colored dots indicate that one or both of the paired data is in the model-inconsistent range. Lines beside the dots show 2-fold (solid green lines) and 1.4-fold (dashed green lines) differences. The number of data used for each plot was 1,500. Data sets were obtained from control hybridizations in Iyer et al.  (panels a and b), and from dye-swap hybridizations in Horvath et al.  (panels c and d).