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Influence of geography on real estate e significant advantage to a geographic centric database is the ability to have not only the integrated information, but the ability to analyze the effect geography has on the value of a property. e example in Figure 5 provides the spatial output (map) of using defined sales to extrapolate and predict the valuations of the unsold properties while representing the market areas for the entire population. In this example, a defined set of sales was used to predict the values of all properties in Maricopa County, which incorporates Phoenix and surrounding cities. Geo-processing is a GIS operation that can be used to process, analyze and manipulate spatially related data. Ultimately, the use of it allows for definition, management and analysis of information which can be used to form decisions and actions. An example of how geo-processing is used can be better understood by the image in Figure 6. In this example, geo- processing (an algorithm) was used to read the ortho image (air photo) and detect where a swimming pool 'might' exist on a property. is layer was then compared to the actual ortho image as well the appraiser's current data set (assessor's data in their CAMA system) to determine where a pool was correctly assessed, or where there was a discrepancy between the assessor's data and what was actually on the ground. is evolution of technology is allowing the user to run an automated process to conduct a check/inspection on property data rather than having to visit each property independently. In this situation, approximately 1,000,000 homes in Maricopa County had this automated review completed in hours through geo-processing vs. the alternative of literally decades of time if an appraiser had to visit each property independently. Where does this technological innovation in real estate software systems end? Is there more? e short answer is that it is not ending and it gets even more sophisticated with the introduction of 3 Dimension (3D) to the equation. 3D is a new and emerging area of GIS technology. As seen in Figure 7, typical 3D work in GIS to date presents cityscapes or scenes that are simple building polygons FIGURE 6 (circled in white) normally extruded from the building footprint. Although nice to look at, this simple type of building polygon and cityscape presents only a visual scene. e practical application, usefulness and value of these simple buildings and the resulting scene are limited for the real estate industry. However, the capability exists to develop a more complex building (circled in red), which, in this example, is comprised of actual strata condominium units that are physically correct to the strata plan and spatially correct to the unit's place on earth. is complex use of 3D GIS will bring more value to the user. FIGURE 7 Volume 59 | Book 3 / Tome 3 | 2015 | Évaluation Immobilière au Canada | Canadian Proper ty Valuation

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