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Data Model


An important aspect when beginning a geospatial project is to decide how the data will be organized. This includes figuring out what attributes you will collect for field observations. At this point, it is helpful to start thinking of questions you may want to answer with your data. This will inform the types and quantity of data you need to gather.

In general, there are four types of data:

  • nominal (qualitative; e.g. male, female, etc.)
  • ordinal (rank order; e.g. first, second, etc.)
  • interval (1,2,3, ...)
  • ratio (similar to interval, but has an absolute zero value)

Each attrubute that you wish to collect will have a corresponding data type. The type of data recorded affects the types of analysis that you can perform. Ratio and interval have the most flexibility in terms of analysis functions, with ordinal and nominal data being more mathematically ambiguous.

Further Reading

Task Discussion