for maximum impact, high yielding improved varieties with significant yield advantages must be targeted to farmers and localities that value this trait most. explaining farmers’ demand for yield can serve as a means of targeting the development and dissemination of high yielding varieties. this paper analyzes data collected from 395 farmers in northern ethiopia using a zero-limit tobit regressi...

In spite of its significance for everyday and philosophical discourse, the explanatory connective ‘because’ has not received much treatment in the philosophy of logic. The present paper develops a logic for ‘because’ based on systematic connections between ‘because’ and the truthfunctional connectives.

We will argue that this construction combines semantic and syntactic quirks that necessitate a constructional analysis. Further, we will show that specifying the pragmatic properties of the construction (and in particular the presuppositions that introduces) allows for a particularly elegant account of the construction’s distribution. This, in turn, provides further support for the sign-based v...

Study of the neutrinoless ββ decay allows us to put a stringent limit on the effective neutrino Majorana mass, a quantity of fundamental importance. To test our ability to evaluate the nuclear matrix elements that govern the decay rate, it is desirable to be able to describe the allowed two-neutrino decay. It is argued that only low-lying virtual intermediate states are important for that proce...