Figure 4From: Estimating front-wave velocity of infectious diseases: a simple, efficient method applied to bluetongueCorrelograms of the residuals from the TSA model (left) and the selected trend SAR err model (right). Correlogram plots Moran's I values on the y-axis against geographic distance in km in the x-axis. Moran's I has an expected value near zero for no spatial autocorrelation, with negative and positive values indicating negative and positive autocorrelation, respectively.Back to article page