Problems:

The first major problem to arise in this project was in data processing. The majority of data were downloaded in ARCINFO format, requiring conversion into raster images. When imported into ARCMap and converted to ARCRaster ASCII files using the same cell resolution for image generation in IDRISI, image dimensions were slightly different. In some case images varied by 1 row or column, however this still prevented any spatial analysis via overlay. Numerous attempts in both IDRISI and ARCMap to reproject the data failed to fix the problem. It is possible that this was due to the unique projection used by the USGS for their Lake Tahoe Data (a combination of US NAD 1927 Zone 10 and 11). This problem was ultimately solved by creating and extensively editing shapefiles in ARCMap and using the SHAPEIDR module in IDRISI for conversion of ARC shapefiles into IDRISI vector layers, with the properties of the USGS DEM used as a blank basemap for import. These were then converted to raster images.

A second problem to arise was the conversion of imported vector layers in line format to shapefiles, or what I refered to as 'the vector line psych-out'. The module LINERAS was used on the input vector layers to produce their raster images. However, the output images were visually unappealing, suggesting that perhaps some data had been lost in the process. This was so severe that the use of these data was questioned. In the end, the decision was made to use the data anyways, and the resulting distance and standardized distance from roads (ie fuzzy) image demonstrated visually that no data had been excluded.

A final problem associated with this project was a general lack of specific knowledge. By this I mean that although criteria for the locational analysis were based on my cumulative knowledge of the situation, they were my personal assumptions. I believe that the analysis would have been much more accurate with more specific knowledge of the costs of construction and the direct impacts of construction etc., rather than just my somewhat informed assumptions.

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