Substantive versus Formal theory – and groups.
If I wanted to do a formal study – I would likely compare agritecture with other forms of agriculture (or precision farming) – to generate a formal theory of food production organisations. If I want to do a substantive study – I would compare within agritecture – i.e. comparing types of agritectures rather than types of farming. It is also possible to combine some amount of the two – perhaps discussing my theory of agritecture whilst contextualising this within farming more generally – or futuristic food production more generally.
Barney G. Glaser & Anselm L. Strauss. 1967. The Discovery of Grounded Theory. London: Weidenfeld and Nicolson.