od_aus                  Example OD dataset: flows between regions in
                        Australia
si_calculate            Calculate flow using a pre-existing function
si_od_census            Example OD dataset
si_predict              Predict spatial interaction based on
                        pre-trained model
si_pubs                 Example destinations dataset: pubs in Leeds
si_to_od                Prepare OD data frame
si_zones                Example zones and centroids
zones_aus               Example zones dataset: regions of Australia
