Returns of an individual enterprise in the short term are usually measured through a gross margin budget, which is determined by subtracting factors such as the cost of weed control (both herbicide and non-herbicide) and other inputs (eg seed and fertiliser) from gross income (calculated as crop yield multiplied by grain price). Crop yield is directly influenced by weed density, which itself is...

In [1] we explained that partition functions of various matrix models can be constructed from that of the cubic Kontsevich model, which, therefore, becomes a basic elementary building block in ”M-theory” of matrix models [2]. However, the less topical complex matrix model appeared to be an exception: its decomposition involved not only the Kontsevich τ -function but also another constituent, wh...

We show that the massless (ultraviolet regularized) Gross-Neveu model, in d 3 dimensions and any number of avors (N = 1; 2; 3; : : :), does not exhibit the mass generation mechanism if the quartic term coupling constant is suuciently small. In particular, extending previous results (rigorously established for N = 1 1,2]) we prove that the two-point function can be written in terms of a converge...

Empirical studies quantifying the benefits of increased foreign direct investment (FDI) have been unable to provide conclusive evidence of a positive impact on host country’s economic performance. I show that the lack of robust evidence is not inconsistent with theory, even if the eventual gains to FDI are large, if restrictions on FDI are lifted only gradually and part of FDI is intangible inv...