We discussed this slightly in the Chatterbox.. These are a few options that would permit position ambiguity:
- Use trailing zeros in the latitude/longitude to represent the degree of ambiguity. While most efficient as far as storing data, this is inaccurate where people actually live at a longitude/latitude that ends in one or more zeros. A workaround would be to put a 1 at the end of the number to force it to be interpreted as a literal precise position. Since we aren't anal about expressing this information in the most efficient method possible, one of the options below is probably more desirable, and less of a "hack".
- Use latitude/longitude, with a "degree of precision" field, either expressed in a radius form (say, I'm within 15 miles of this location), or representing the number of significant digits in the latitude/longitude.
- Use latitude/longitude for those that want to be precise, but make an alternate method available for those that don't. Things such as grid square references are standard ways of referring to manageable areas of land that still provide enough information to tell what city (or what area of a city) a person lives in.
- Use an ambiguous method to deal with everyone's position. This would be simplest/most efficient, but would prevent anyone from specifying a precise location. A simple text field for a grid square reference would be adequate.
There are also other means of identifying location, such as area codes, zip codes, city names, etc.