A comparison of programming languages in macroeconomics

We solve the stochastic neoclassical growth model, the workhorse of modern macroeconomics, using C++14, Fortran 2008, Java, Julia, Python, Matlab, Mathematica, and R. We implement the same algorithm, value function iteration, in each of the languages. We report the execution times of the codes in a Mac and in a Windows computer and briefly comment on the strengths and weaknesses of each language.     

HIS系统药品动态流动和结构的研究

药品动态流动是医院计算机管理中的一个重要组成部分,合理设置药品流动的动态管理既可以方便医院的自主使用．又可以避免软件开发人员频繁地改动程序。针对医院管理系统中药品动态流动的问题,应用集中参数表方式设定药品动态流动结构的思想和基表结构．解决了药品动态流动中的问题,效果良好。     

Price-raising drug enforcement and property crime: a dynamic model

Price-raising drug enforcement suppresses drug use, but it is expensive and may increase property crime. This has led to contradictory recommendations concerning how drug enforcement should or should not be used. We reconcile these recommendations by incorporating the enforcement's effects on both drug use and on property crime within an optimal-control model that recognizes whether convicted drug-involved property offenders are merely incarcerated or whether they receive some form of drug treatment.     

Stackelberg equilibrium with many leaders and followers. The case of zero fixed costs

I study a version of the Stackelberg game with many identical firms in which leaders and followers use a continuous cost function with no fixed cost. Using lattice theoretical methods I provide a set of conditions that guarantee that the game has an equilibrium in pure strategies. With convex costs the model shows the same properties as a quasi-competitive Cournot model. The same happens with concave costs, but only when the number of followers is small. When this number is large the leaders preempt entry. I study the comparative statics and the limit behavior of the equilibrium and I show how the main determinants of market structure interact. More competition between the leaders always displaces the followers. Instead, how a stronger threat of entry affects the equilibrium depends on the technology. With strictly convex costs it is the followers that eventually displace the leaders.     

Market power in input purchase and trade

Market power in the input purchase is becoming increasingly common because of growing consolidation and mergers and also due to multinational firms establishing a stronghold in buying inputs in the developing countries. In this study, we formulate a general equilibrium model consisting of a competitive sector and an oligopsony sector which exercises market power over inputs. Our results indicate that if the oligopsony sector incurs a higher marginal factor cost for the intensive factor, basic results of the standard two-sector model continue to hold. But if the marginal factor cost is higher for the non-intensive factor, then factor intensities in the physical and value sense differ and traditional trade propositions such as the Stolper–Samuelson theorem do not hold.     

Dynamic modelling of pollution abatement in a CGE framework

This paper deals with the specification of pollution abatement in dynamic computable general equilibrium (CGE) models and analyses the dynamic feedback mechanisms between economy and abatement in the context of environmental policy. A Ramsey-type economic model is presented, in which bottom-up technical and economic information on abatement techniques is integrated in a top-down dynamic CGE context. The practical suitability of the specification is illustrated by an empirical application for climate change and acidification in the Netherlands. The results show that a mixture of some slowdown of economic growth, a substantial restructuring of the economy and implementation of most technical abatement measures is optimal.