The Narrow and Broad Approaches to Evolutionary Modeling in Economics

Some models in evolutionary economics rely on direct analogies to genetic evolution, assuming a population of firms with routines, technologies, and strategies on which forces of diversity generation and selection act. This narrow conception can build upon previous findings from evolutionary biology. Broader concepts of evolution allow many or just one adaptive entity, instead of necessarily requiring a population. Thus, an institution or a society can also be understood as an evolutionary entity. Both the narrow and broad approaches have been extensively used in the literature, albeit in different literature traditions. I provide an overview of the conception and development of both approaches to evolutionary modeling, and argue that a generalization is needed to realize the full potential of evolutionary modeling.     

Temporal stability of preferences and willingness to pay for natural areas in choice experiments: A test–retest

The main objective of this paper is to test the temporal stability of stated preferences and willingness to pay (WTP) values from a Choice Experiment (CE) in a test–retest. The same group of participants was asked the same choice tasks in an internet-based CE, conducted twice with a time interval of one year without interviewer interference. We examine choice consistency at individual choice task level and transferability of the underlying indirect utility function and associated WTP values. The results show that choices are consistent in 57 percent of the choice occasions. Comparison of the choice models over time shows that the estimated preference and scale parameters are significantly different, suggesting that choice behaviour changed between the two surveys. Differences between marginal WTP estimates for individual choice attributes are statistically significant only at the 10 percent level. However, we show that this can result in significantly different WTP values for policy scenarios. The instability of estimated mean WTP values for different policy scenarios asks for caution when including WTP values in cost-benefit analysis.     

China's macroeconomic stability – an empirical study based on survey data

A complete financial stability analysis should include investigation on macroeconomic stability since macroeconomic development and potential imbalance can increase the financial instability and trigger a financial crisis. Survey data of rating on China's macroeconomic stability is analyzed by estimating an ordered logit model with random effect. Among the candidate macroeconomic indicators, we found that inflation is the key variable that determines China's macroeconomic stability, followed by the change in budget balance and GDP growth gap.     

价值工程在特大型不锈钢封头制造中的应用

在对太空模拟训练仓中的特大形不锈钢封头制造中,运用了价值工程手段,并创新采用近似椭圆参数(R=0.8415D和r=0.1285D)和椭圆形封头顶圆的足球瓣结构,产品质量满足要求且降低了成本。     

对某古滑坡稳定性分析的探讨

古滑坡是一种不良地质现象,易诱发为地质灾害,对人类生命财产安全造成危害。本文以某古滑坡工程勘察实例为基础,对其成因及稳定性进行了分析评价,最后笔者得出了该古滑坡处于稳定状态,对工程影响不大,从而节约了工程投资。     

变电站岩溶地基的勘察设计与地基基础处理

结合湖北省某变电站在岩溶发育地基上成功建站的工程实践，介绍了岩溶地基的勘察方案、岩溶发育的规律及机理、岩溶地基的稳定性评价、岩溶发育地区变电站站址地基基础的处理以及设计中应注意的事宜等内容。实践证明：在一定的条件下，只要地基基础处理时采取的措施得当，在岩溶发育的灰岩地基上仍可修建变电站。     

Measuring market distortion: international comparisons,policy and competitiveness

This paper develops a framework to simultaneously estimate production possibility frontiers and measure distortions in factor and product markets. The econometric results, based on a panel of 61 countries over the period 1970 through 1985, reveal very little distortion in factor markets but considerable distortion in product markets. In addition, the distortions tend to vary with the cyclical behaviour of economic activity. Further, the results suggest that in order to improve efficiency, commercial policy should aim at reducing product-market distortions rather than factor-market ones.     

The Output Effect of a Transition to Price Stability When Velocity Is Time Varying

This paper explores the effect of time‐varying velocity on output responses to policies for reducing/stopping inflation. We study a dynamic general equilibrium model with sticky prices in which we introduce time‐varying velocity. Specifically, we endogenize time‐varying velocity into the model developed by Ireland (1997) for analyzing optimal disinflation. The nonlinear solution method reveals that, depending on velocity, the “disinflationary boom” found by Ball (1994) may disappear even under perfect credibility and that early output losses may be much larger than previously thought. Indeed, we find that a gradual disinflation from a low inflation may even be undesirable.