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  2. Grid (spatial index) - Wikipedia

    en.wikipedia.org/wiki/Grid_(spatial_index)

    The use of such spatial indices is not limited to digital data; the "index" section of any global or street atlas commonly contains a list of named features (towns, streets, etc.) with associated grid square identifiers, and may be considered a perfectly acceptable example of a spatial index (in this case, typically organised by feature name ...

  3. R-tree - Wikipedia

    en.wikipedia.org/wiki/R-tree

    Simple example of an R-tree for 2D rectangles Visualization of an R*-tree for 3D points using ELKI (the cubes are directory pages). R-trees are tree data structures used for spatial access methods, i.e., for indexing multi-dimensional information such as geographical coordinates, rectangles or polygons.

  4. Spatial database - Wikipedia

    en.wikipedia.org/wiki/Spatial_database

    A spatial index is used by a spatial database to optimize spatial queries.Database systems use indices to quickly look up values by sorting data values in a linear (e.g. alphabetical) order; however, this way of indexing data is not optimal for spatial queries in two- or three-dimensional space.

  5. Geohash - Wikipedia

    en.wikipedia.org/wiki/Geohash

    For example, the coordinate pair 57.64911,10.40744 ... For exact latitude and longitude translations Geohash is a spatial index of base 4, ...

  6. Moran's I - Wikipedia

    en.wikipedia.org/wiki/Moran's_I

    The fact that Moran's I is a summation of individual cross products is exploited by the "local indicators of spatial association" (LISA) to evaluate the clustering in those individual units by calculating Local Moran's I for each spatial unit and evaluating the statistical significance for each I i.

  7. Quadtree - Wikipedia

    en.wikipedia.org/wiki/Quadtree

    An example of a recursive binary space partitioning quadtree for a 2D index. Quadtrees may be classified according to the type of data they represent, including areas, points, lines and curves. Quadtrees may also be classified by whether the shape of the tree is independent of the order in which data is processed.

  8. Spatial weight matrix - Wikipedia

    en.wikipedia.org/wiki/Spatial_weight_matrix

    The concept of a spatial weight is used in spatial analysis to describe neighbor relations between regions on a map. [1] If location i {\displaystyle i} is a neighbor of location j {\displaystyle j} then w i j ≠ 0 {\displaystyle w_{ij}\neq 0} otherwise w i j = 0 {\displaystyle w_{ij}=0} .

  9. Spatial descriptive statistics - Wikipedia

    en.wikipedia.org/wiki/Spatial_descriptive_statistics

    An example of gridded data would be a satellite image of forest density that has been digitized on a grid. An example of a point set would be the latitude/longitude coordinates of all elm trees in a particular plot of land. More complicated forms of data include marked point sets and spatial time series.