Figure 12From: Probing crowd density through smartphones in city-scale mass gatheringsResidual analysis. (a) Residual plot of the estimated crowd density to the actual crowd density for the two kernel radii R=10 m and R=55 m. (b) The normal probability plot of the residuals. The good linearity of the regression supports the chosen model. (c) The histogram of the residuals shows a normal distribution.Back to article page