background and objectivesintercropping or simultaneous growing of two or more crops on the same piece of land has the potential of enhanced ecosystem productivity. in a cereal-legume intercropping system, an increase in cereal and a decrease in legume intercrop yield is reported. several indices such as land equivalent ratio (ler), relative crowding coefficient (k), competitive ratio (cr), aggr...

This paper presents a new method of measuring performance when positives are rare and investigates whether Chomsky-like grammar representations are useful for learning accurate comprehensible predic-tors of members of biological sequence families. The positive-only learning framework of the Inductive Logic Programming (ILP) system CPro-gol is used to generate a grammar for recognising a class o...

Suppose individuals get utilities from the total amount of wealth they hold and from their wealth relative to those immediately below them. This paper studies the distribution of wealth that maximizes an additive welfare function made up of these utilities. It interprets wealth distribution in a control theory framework to show that the welfare maximizing distribution may have unexpected proper...

this study investigated the export status of stone fruits in iran during 1997 to 2010.export trends and revealed comparative advantage of indices, namely, revealedcomparative advantage (rca), revealed symmetric comparative advantage (rsca),and relative export advantage (rxa) as well as trade mapping (tm) were investigatedfor cherries, plums, peaches, and apricots. target markets for these produ...

When faced with a variable environment, organisms may switch between different strategies according to some probabilistic rule. In an infinite population, evolution is expected to favor the rule that maximizes geometric mean fitness. If some environments are encountered only rarely, selection may not be strong enough for optimal switching probabilities to evolve. Here we calculate the evolution...

With higher payments and expanded private-plan authority, Medicare Advantage (MA) has caused the market to grow. One in three Medicare beneficiaries with Part D now gets this coverage through MA. Analysis of the sources of and reasons for enrollment growth suggest a troubling report card. Clearly, the Medicare Modernization Act (MMA) has expanded choice and the private-sector role. But it also ...

in order to evaluate the yield and advantage of two- and three-species intercropping of sunflower with corn and soybean, an experiment was conducted at the research farm of faculty of agriculture of tabriz university in tabriz, iran 2011. the experiment was arranged based on randomized completely block design with 6 treatments and three replications. treatments were included the pure stand of s...

The Medicare Advantage (MA) program continues to grow and thrive, despite plan payment cuts imposed through the Affordable Care Act. What explains this surprising outcome (one that is strikingly different than the experience of MA plans in the late 1990s, when payment cuts led to dramatic shrinkage in enrollment and curtailment of plans)? This analysis argues that a combination of factors, incl...

Sustainable competitive advantage (CA) is a necessary requirement of a rational economic business organisation. Without this CA a business does not have a rational source for appropriating added value in the form of retained profit. Various management research papers have identified numerous factors that may create a source of competitive advantage. Other researchers have shown how industries h...