Hexagons are preferable when your analysis includes aspects of connectivity or movement paths.This means that any point inside a hexagon is closer to the centroid of the hexagon than any given point in an equal-area square or triangle would be (this is due to the more acute angles of the square and triangle versus the hexagon). When comparing polygons with equal areas, the more similar to a circle the polygon is, the closer to the centroid the points near the border are (especially points near the vertices).This circularity of a hexagon grid allows it to represent curves in the patterns of your data more naturally than square grids.Hexagons are the most circular-shaped polygon that can tessellate to form an evenly spaced grid. A circle has the lowest ratio but cannot tessellate to form a continuous grid. Hexagons reduce sampling bias due to edge effects of the grid shape, this is related to the low perimeter-to-area ratio of the shape of the hexagon.Reasons to consider aggregating into a hexagon grid are the following: Though the square (fishnet) grid is the predominantly used shape type in GIS analysis and thematic mapping, there are ways in which hexagons may be better suited for your analysis based on the nature of your question. Triangles, squares, or hexagons, as these three polygon shapes are the only three that can tessellate (repeating the same shape over and over again,Įdge to edge, to cover an area without gaps or overlaps) to create Regularly shaped grids can only be comprised of equilateral The aggregation of incident point data to regularly shaped grids is used for many reasons such as normalizing geography for mapping or to mitigate the issues of using irregularly shapedĬounty boundaries or block groups that have been created from a political process).
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