Sonis and Grossman (1984) introduced a semilogarithmic model for rank-size rule for explaining rural settlements. Does any one know are there any other models?
I would use the head/tail breaks to differentiate urban settlements and rural settlements from all natural cities, i.e., those above the average in the head are urban settlements, and those below the average in the tail are rural settlement.
Jiang B., Yin J. and Liu Q. (2015), Zipf’s Law for all the natural cities around the world, International Journal of Geographical Information Science, 29(3), 498-522.
Dear Xuefeng, I know that aside from the rank-size model ,there was a rule of thumb applied in many countries which was 5000people, less than that rural, more urban. This number varies in different countries, those with more population increased the number and less populated countries have smaller numbers. In some countries though the criteria to distinguish a settlement as urban or rural has changed and it is not based just on the population any more but in other factors including having or not having a municipality, the national/regional roles and responsibilities and the level of governmental support. For example a settlement may have less population comparing to other urban areas but as it is a tourist hub(has the national role of tourist attraction) and has a municipality it is considered an urban settlement therefore it gets governmental budget ;some settlements may have merely one of these roles as political or religious or educational or entertainment roles and they are considered urban too. So it depends on the strategic national plannig of that country. Sorry that I cannot recall what it was called if it was a model.