Distribution of log
ratio differences between conditions for all four tumors. Distributions of log10 ratio differences for the 182 of the 232 genes that had signals significantly above background (signals > 15) are plotted. Each set of log10 ratios were compared with another set by subtracting the log10 ratios of one set from those of the other to get a set of 182 log10 ratio differences. The green distributions compare arrays with the same labeled sample, hybridized in different laboratories. The blue distributions compare arrays labeled at different locations but hybridized at the same location. The black distributions compare arrays with different labeled samples, hybridized in different locations. Each curve is a probability distribution (normalized histogram) of the differences between the average log10 ratios of the 182 probes in one condition, and their average in the other condition.