This paper explores the role of contract farming arrangements in agricultural intensification sub-Saharan Africa, combining secondary literature and original case material from Mozambique. The extends scope “contract farming” beyond formal contracts between large companies small-scale producers to include less credit agreements farmers traders. It argues that such informal are evidence farmers'...

Current interests in the context of system development include non-functional aspects of an application and the quality of the service (QoS) it provides. In video on demand applications, for instance, properties such as delay, bandwidth and CPU utilization are monitored in order to identify if they are within acceptable limits. In our approach, non-functional requirements are described by contr...

In software developers’ world two aspects are common knowledge: software fails are expensive, so we need reliable software; software itself is expensive, so we want reusable software. Design by Contract, advocated by Bertrand Meyer, is known as one of the most comprehensive methods for ensuring reliability, while delivering reusable software components. A business component is a component that ...

Formal methods and testing are often considered as disjoint technologies. The Hi-Lite project wants to show that both are actually complementary. The central concept are subprogram contracts, part of the upcoming Ada 2012 standard. A contract, which consists of preand postcondition, describes the specification of a subprogram, in the same syntax as Ada expressions. These contracts can be seen e...

We understand by a contract a document written in natural language which engages several parties into a transaction, and which stipulates commitments (obligations, rights, and prohibitions) of the parties. Moreover the contract specifies also reparations in case of contract violation (i.e. some obligations or prohibitions are not respected). Because the human language is ambiguous by nature, co...

This paper analyzes contactual situations between many principals and many agents. Agents have private information and principals take actions. Principals can contract not only on the reports of the agents but also on the contracts offered by the other principals. Contracts are required to be representable in a formal language. The main result of the paper is a full characterization of the allo...

The ability to buy “empty votes” by using derivative contracts to separate shares’ voting and cash flow rights is a cause of policy concern. We construct a formal model of a market for empty votes where informed and uninformed (and potentially biased) shareholders endogenously choose to demand or supply. There always exists an equilibrium where only informed shareholders demand votes, since uni...

Weprovide a generalmechanism for obtaining uniform information from pointwise data. A sample result is that if a diffeomorphism of a compact Riemannian manifold has pointwise expanding and contracting continuous invariant cone families, then the diffeomorphism is an Anosov diffeomorphism, i.e., the entire manifold is uniformly hyperbolic.

This paper studies the effectiveness of interim information in reducing inefficiencies in long term relationships. If the interim information is verifiable, it resolves all problems of asymmetric information. Under nonverifiability, the information alleviates the contracting problem only partially and its optimal use depends on the signal’s accuracy and timing. Precise and early signals enable ...