Why are there separate supply and market modules in CAPRI?
There are several reasons. Firstly, the different modules can be maintained and improved indepedently. Secondly, different methodological solutions can be chosen. The supply side is based on explicit profit optimisation under constraints, which has e.g. adventages when capturing the effect of policy instruments as quotas or set-aside or linking it to engineering data or results from bio-physical models. The international trade model is a square system of equations based on behavioural functions, which allows to capture many products, market and interactions simultaneously. Thirdly, it would be most probably technically not feasible to solve the whole system as one supermodule. And not at least, you may use the supply side of CAPRI indepedent from the market models for analysis, even running the system for single countries, only.
