Abstract: | A new method is proposed to map firms' principal market areas using shipment data. The new method is a general one which could prove just as useful in mapping the incidence of disease as in mapping market areas. This method is applied to agricultural data for feeder cattle sales at a video cattle auction. Transportation costs appear to be the main determinant of market area boundaries, but there are many cases where transportation costs alone cannot explain the market areas found. The size and shape of market areas for feeder cattle buyers are large, irregularly shaped, and extensively overlapping. |