13. What are grain reserves worth? A generalised political economy framework

What explains volatility in world food prices? Are the “fundamentals” of supply and demand the basic factors? Can national or international policies toward food grain reserves help to stabilize food prices? What are food stocks “worth” if the levels of grain reserves, especially in large countries, affect food trade policies in these countries? This effect would be the reverse of the usual causation where policies can directly affect the levels of both public and private stocks.