Spatial Analysis / Results

          The constraints and factors were used to determine the suitable locations for an indoor pocket bike race track. Multi-criteria Evaluation (MCE) is a process for assessing and aggregating many criteria using a weighted linear combination. In order to do a Multi-Criteria Evaluation I selected "Decision Wizard" from the "GIS Analysis"-->"Decision Support" and went through all the necessary steps.

          A pairwise comparison matrix using the Analytical Hierarchy Process was used to determine the importance of factors in choosing the suitable locations for a pocket bike race track. Basically a pairwise comparison is a weight module in IDRISI in which it uses the values in the Analytical Hierarchy Process but makes two copies of it. If you look at the table below you will see the pairwise comparison module that I have created. The first column to the left displays all the factors where as the first row displays the same factors but it goes across the row instead and in the same order as the factors going down the first column. The reason to use this pairwise comparison is that not all the factors will have the same importance from one another. And so, by assigning a value to each factor that is compared to another factor, IDRISI will understand what factors are more important and what factors are not as important and will generate a result based on your assigning. This is also refered to as weighting certain factors to be more important than the other factors. An example would be that I assigned a value of 3 for residents to shops. According to the pairwise comparison module, it states that a value of 3 means "moderately more important". And the reason I assigned it a value of 3 is because of this and that I want residentail areas to be as close to shops as possible so that the facility can be built within these areas. Most of my factors were assigned a value of 1 as they were equally weighted amongst one another and other comparable factors were assigned a greater value due to thier importance.

Pairwise Comparison Module

          As long as the Analytical Hierarchy Process was determined to be consistent, a MCE for the suitable locations of an indoor pocket bike race track will be generated. In IDRISI, the consistency ratio has to be acceptable as in the numeric values that were entered, have to meet the minimum requirement for MCE to run the analysis and to generate a result. And so my consistency ratio was determined to be 0.8 and consistent thus generating a map of Langley which displays the suitable locations in a color range of 0 to 255 with 255 or "purple" being the most suitable.

MCE map of suitable areas was generated as long as the consistency ratio was acceptable.

          The best suitable locations were found to be along the Trans Canada #1 Hwy roughly around 80th Avenue and 192nd Street in Langley. The best results module was used to find the open and undeveloped land that was 0.55 hectaries big for this facility to be built on. The results were several points closely clusted amongst each other. This area in Langley would be the most suitable location for my indoor pocket bike race track as it is close to residential areas and within close proximity to retail stores that sell pocket bikes. Plus, all the other factors fit the requiremetns as well. It is on open and undeveloped land and within the average total population and has a road network which provides high accessibility for people coming to this facility from elsewhere around the GVRD.

Finding the best locations with a constraint of finding 0.55 hectares of open land within the suitable areas to build facility thus generating various locations for the best sites that meet the requirement to build on including a zoomed in view of the area with various point locations.

 

          The cartographic model in IDRISI lets you add modules and raster or vector files to be manipulated by operations such as these modules. With a cartographic model, it lets the user view the operations he or she is using to manipulate a certain raster or vector file. This means that you can input many operations such as many reclasses to just one raster land-use file just like what I did in my cartographic model. And when there is an incorrect operation with wrong variables done to a certain raster or vector file, this model will tell the user that the operation is wrong and has to be edited in order for the model to function properly. Basically the cartographic model lets the user see a "map" of the operations that he or she has done in order to produce a final result.

My Cartographic Model: