Changes

Objectives: Understanding of interpolation as part of spatial analysis

:[http://docs.qgis.org/2.2/en/docs/gentle_gis_introduction/spatial_analysis_interpolation.html Interpolation]

:[http://opensourcegisblog.blogspot.ch/2015/03/spatial-analysis-with-qgis-part-i-point.html Point Data]

Spatial Analysis with QGIS - Points in Polygon