Figure 6

Privacy-preserving regression diagnostic plots of data from dataset D2. (A) Residuals against fitted values; (B) Normal QQ plots; (C) Residuals against leverage. From left to right we demonstrate the plots: (i) for real regression outcomes; (ii) the regression outcomes aggregated in a 30 by 30 density grid matrix and suppressing any grids with density less than three counts; (iii) the regression outcomes aggregated in a 15 by 15 density grid matrix and suppressing any grids with density less than three counts; (iv) the scaled centroids of each 3-nearest neighbours of the regression outcomes obtained by deterministic anonymization; (v) the noisy regression outcomes obtained by probabilistic anonymization. Note that for plots B and C we use the standardized residuals that are the residuals divided by their standard deviation