tailieunhanh - KEY CONCEPTS & TECHNIQUES IN GIS Part 2

Một phần của vấn đề là nó dễ dàng hơn nhiều để nói về hữu hình như dữ liệu như là một loại hàng hoá, và các thủ tục số hóa hơn để khái quát những gì phải là bước đầu tiên: một phân tích về những gì cần thiết để giải quyết một câu hỏi cụ thể địa lý. | 1 Creating Digital Data The creation of spatial data is a surprisingly underdeveloped topic in GIS literature. Part of the problem is that it is a lot easier to talk about tangibles such as data as a commodity and digitizing procedures than to generalize what ought to be the very first step an analysis of what is needed to solve a particular geographic question. Social sciences have developed an impressive array of methods under the umbrella of research design originally following the lead of experimental design in the natural sciences but now an independent body of work that gains considerably more attention than its counterpart in the natural sciences Mitchell and Jolley 2001 . For GIScience however there is a dearth of literature on the proper development of applied research questions and even outside academia there is no vendorindependent guidance for the GIS entrepreneur on setting up the databases that off-the-shelf software should be applied to. GIS vendors try their best to provide their customers with a starter package of basic data but while this suffices for training or tutorial purposes it cannot substitute for in-house data that is tailored to the needs of a particular application area. On the academic side some of the more thorough introductions to GIS . Chrisman 2002 discuss the history of spatial thought and how it can be expressed as a dialectic relationship between absolute and relative notions of space and time which in turn are mirrored in the two most common spatial representations of raster and vector GIS. This is a good start in that it forces the developer of a new GIS database to think through the limitations of the different ways of storing and acquiring spatial data but it still provides little guidance. One of the reasons for the lack of literature - and I dare say academic research -is that far fewer GIS would be sold if every potential buyer knew how much work is involved in actually getting started with one s own data. Looking from