Figure 4From: Quantile regression for the statistical analysis of immunological data with many non-detectsTrend for the 75th percentile (P75) of IL-10 with age. Legend: The data points have been "jittered" (a random horizontal shift between −0.2 and 0.2) for better visibility. The full line is obtained by quantile regression on age only, the broken line with the observation time point as an additional factor.Back to article page