SPATIAL INTERACTION MODELS – Richard Harris, Peter Sleight, Richard Webber

How the following retail question might be answered within a GI analytical environment? Suppose a consumer lives at location i (to be found at coordinate xi, yi)?

To answer this question, two ideas seem intuitive. First, that the attraction of the store to the consumer depends on what the store has to offer. This we shall quantify as the store’s mass (Mj), for reasons that will become clear. Second, that the consumer would prefer to travel a shorter distance to visit a store than a longer one and so the attraction of the store is related to the distance between locations i and j. These two assumptions allow the following spatial interaction model to be formed:

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A short ESRI animation explaining Geographic Information Systems in a specially didatic way. GIS is a system to record, analyze and present spatial information on maps, allowing better decision making using geography. Traders use GIS to choose the location of new stores to sell specific products to the local public. It’s used by environmental organizations to mitigate the consequences of global warming. Electric companies use to locate specific parts that need repairs and to do them more efficiently. The police use it to identify patterns in criminal activities and plan operations more strategically. View information and trends is much easier on maps than spreadsheets. GIS is a software that runs on computers connected to powerful servers, which can now be accessed even by smartphones. GIS are informations about the real world divided into layers. Each layer contains informations of the same type. Continue reading WHAT IS GIS?