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I was wondering if you could help me answer a few questions about the Proximity Toolset. I have been given the task of describing each tool in laymen terms, the typical usage of each tool, and most importantly, the limitations of each tool.

So far, these are the only limitations that I have found:

1. Buffer Tool: Buffering across large regions and datasets, display performance issues when drawing or editing buffers

2. Thiessen's Polygons: The polygons are not created based on event importance and there is no facility to weight each point. Polygons can be impacted if the topography of the land changes across the study area.

3. Generate Near Table Tool and Near Tool: Point Distance will not work if either coverage contains more than 130,000 points

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+1 Weighting sure would be a nice option for Thiessen polygons, more commonly known as Multiplicatively Weighted Voronoi Diagram –  Kirk Kuykendall Mar 23 '11 at 15:31
    
On the buffer tool the Dissolve option can have particular problems when used with a large number of closely packed features. –  Matthew Snape Mar 23 '11 at 15:45
    
@Kirk Any software that can draw "trade areas" using a gravitational model (Reilly or Huff) is actually drawing weighted Voronoi tessellations. –  whuber Mar 23 '11 at 16:00
    
How can topography (a 3D feature) possibly affect Thiessen polygons (a strictly 2D construction)? // You might want to distinguish inherent limitations from incidental limitations: the first is due to the finiteness of space and time while the second is a (correctable) aspect of the algorithm. E.g., with point distance matrices, 130,000 points have 2^33 distances: computing them might hit boundaries of CPU speed, disk storage, file formats, and possibly even address spaces. Those are inherent limitations of the computing system. –  whuber Mar 23 '11 at 16:05
    
Thank you all for your answers, they were especially useful when writing my report. However, I don't think I can choose one answer over others as you all helped me to come up with the various limitations for all tools. –  Diego R Mar 25 '11 at 14:49
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