GISmatters specializes in quantitative location analysis for business,
communications, municipal, environmental, medical, safety, and academic
applications. We apply a rich set of GIS and geostatistical methodologies
and tools to answer your questions about the spatial relationships among
the data crucial to your enterprise.
Location Analysis: Weighting
Many people know that the geographic "center"
of the lower 48 states of the U.S. is at Meade's Ranch in northern
Kansas - there's as much area of the country to the east of that point
as there is to the west, and as much area north as south.
Another way to think of it is as the "balance point",
the place you would put your finger beneath a cardboard cut-out
of the country to make it balance.
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There are many other "centers" of
the country that can be thought of similarly and calculated with
GIS tools. The map above shows a few of them in addition to the
geographic one (white marker): population (red), agriculture (green),
and topography (orange). Each of these is another balance point of
the lower 48 states, but weighted by population, or area under cultivation,
or elevation instead of simply area.
The blue-to-red shading of the map indicates low-to-high
population density on a county-by-county basis.