This paper presents a competitive rational expectations model of spot and forward prices for multiple commodities that can be stored and/or converted. As a result of the conversion option, an equilibrium theory of basis spreads across commodities is derived. This extends the "theory of storage"...

We develop an equilibrium model of the term structure of forward prices for storable commodities. As a consequence of a nonnegativity constraint on inventory, the spot commodity has an embedded timing option that is absent in forward contracts. This option's value changes over time due to both...