A new subpixel mapping (SPM) algorithm combining pixel-level and subpixel-level spatial dependences is proposed in this letter. The pixel-level dependence is measured by the spatial attraction model (SAM) with either surrounding or quadrant neighbourhood, while the subpixel-level dependence is characterized by either the mean filter or the exponential weighting function. Both pixel-level and subpixel-level dependences are then fused as the weighted dependence in the constructed objective function.

This paper aims at analysing the extent to which spatial data are accessed and shared among stakeholders. It also uses Social Network Analysis to investigate institutional and individual behaviour in that process. Finally, it investigates the level of cooperation of all involved actors towards Spatial Data Infrastructure development. Results showed that public and private organizations have been individually engaged data collection and management. However, they are still using different standards and this has led to some disparities in terms of spatial data quality.