Figure 1
From: Preprocessing differential methylation hybridization microarray data
MA plot of one array with three LOESS curves. The blue line is the LOESS curve based on all biological probes. The red dots are 199 internal control probes. The red line is the LOESS curve obtained only using these internal control probes. The cyan line is the weighted LOESS curve (i.e., composite LOESS) curve based on both all biological probes and 199 internal control probes.