ABSTRACT
This chapter concentrates on developments within individual disciplines and appraises how these might be used in quantitative planning. It mainly concerns models of the actual situation, although prediction and policy evaluation are mentioned. Quantitative and mathematical formulation does not ensure that a model will necessarily be a good one, but it does offer an easier means of checking the logical consistency of many non-mathematical models. The chapter attempts to illustrate the main types of models and techniques, although the coverage is by no means comprehensive. A good set of models and techniques already exist for rural and regional analysis which serves a wide variety of purposes and problems. The application of such techniques would permit planning problems to be analysed in a scientific way. Models have the advantage of requiring assumptions to be explicit and evidence to be presented, and they rely on types of evidence and analytical methods which can be challenged, validated or rejected by others.
