基于系统动力学的房地产调控政策动态仿真模型

从供需两个方面综合分析了土地政策、税收政策和金融政策对我国房地产市场的影响路径和传导机理。运用系统动力学分析原理,构建了房地产调控政策动态分析模型,并利用计算机软件进行仿真模拟。对拟实施政策效果进行比较分析的结果显示:土地政策对我国房地产市场的影响最大,税收政策对房地产供给市场的影响比对需求市场的影响大;同时调节利率工具和信贷工具变量,金融政策仍对我国房地产市场的影响不大。最后提出,我国应将调控供给作为调控房地产市场的重点。     

创业市场信心与创业行为关系的动态解析 ——基于GEM与WBD的混合横截面数据的经验证据

本文以行为理论为基础,从动态视角出发,探讨完整经济周期下,创业者创业市场信心与创业行为间关系的变化趋势。同时,分析创业者所处国家的经济发展水平与发展导向及自身社会经济地位在创业市场信心对创业行为正向作用变化趋势中的调节效应。本文根据2006—2015年全球创业观察（GEM）与世界银行数据库（WBD）,构建混合截面数据来探索创业者创业市场信心的反应及其差异。研究发现：(1)在经济衰退期内,创业市场信心对创业行为的正向作用会显著减弱。在随后的经济扩张初期,创业市场信心对创业行为的正向作用会明显增强;(2)处于发展中国家及高经济外向度国家的创业者,创业市场信心对创业行为的正向作用的减弱与增强均会更加剧烈。另外,补充研究发现：(3)仅在经济扩张初期,创业者社会经济地位能积极调节时间对创业市场信心与创业行为间关系的调节效果。本文揭示了创业市场信心与创业行为间关系的变化趋势及该变化产生的边界条件,在一定程度上丰富了创业心理驱动要素对创业行为影响的动态研究,并促进实践界关注经济衰退对创业市场信心冲击而带来的创业活动萎靡的潜在风险。     

Price Dynamics in a Vertical Sector: The Case of Butter

We develop a reduced-form model of price transmission in a vertical sector, allowing for refined asymmetric, contemporaneous and lagged, own and cross-price effects under time-varying volatility. The model is used to investigate the wholesale-retail price dynamics in the U.S. butter market. The analysis documents the nature of nonlinear price dynamics in a vertical sector. It finds strong evidence of asymmetric retail price responses, both in the short term and the longer term, but only weak evidence of asymmetric wholesale price responses. Asymmetric retail responses play a major role in generating a skewed distribution of butter prices. The empirical results indicate the presence of imperfect competition at the retail level.     

Analysing tax evasion dynamics via the Ising model

We develop a model of tax evasion based on the Ising model. We augment the model using an appropriate enforcement mechanism that may allow policy makers to curb tax evasion. With a certain probability tax evaders are subject to an audit. If they get caught they behave honestly for a certain number of periods. Simulating the model for a range of parameter combinations, we show that tax evasion may be controlled effectively by using punishment as an enforcement mechanism.     

UNDERSTANDING THE FINANCIAL CONSEQUENCES OF THE BULLWHIP EFFECT IN A MULTI‐ECHELON SUPPLY CHAIN

This article is concerned with how supply chain strategies can mitigate the Bullwhip Effect and inflated inventories from the perspective of the central firm (typically a manufacturer) in the supply chain. We first outline a base case scenario with a validated system dynamics simulation model, using supply chain characteristics as reported by a real firm, in this case a Mexican electronics supplier to U.S. automobile assemblers. We find, surprisingly, that a lower Bullwhip Effect Index (BE) does not always lead to lower costs in the supply chain studied. Furthermore, sensitivity analysis suggests some interesting, counterintuitive results. The implications of these findings are further developed as we test how lead time reduction can also reduce the Bullwhip Effect in the simulated setting.     

A baseline model of industry evolution

The paper analyses some general dynamic properties of industries characterized by heterogeneous firms and continuing stochastic entry.After a brief critical assessment of some significant drawbacks of recent contributions to modeling of stochastic industrial dynamics, we propose a novel analytical apparatus able to derive some generic properties of the underlying competition process combining persistent technological heterogeneity, differential growth of individual firms and turnover. The basic model, we suggest, is indeed applicable with proper modifications to a large class of evolutionary processes, well beyond industrial dynamics.JEL Classification: L11, O30, C60Support to this research by the International Institute for Applied Systems Analysis (IIASA), Austria; the Fujitsu Research Institute for Advanced Information (FRI), Japan; the Italian National Research Council (CNR), the Italian Ministry of Education, University and Research (MIUR, prot. 2002132413 003) and the Free University of Bozen Bolzano, Italy, is gratefully acknowledged. Comments by Andrea Bassanini, Francesca Chiaromonte, Steven Klepper, Uwe Cantner, Drew Fudenberg and the anonymous referees helped in shaping the paper to its present form. Mariele Berté provided the computer simulations of the model. The usual caveats apply.Correspondence to: G. Dosi     

Let chaos reign,then rein in chaos—repeatedly: managing strategic dynamics for corporate longevity

Combining longitudinal field research and executive experience, we propose that corporate longevity depends on matching cycles of autonomous and induced strategy processes to different forms of strategic dynamics, and that the role of alert strategic leadership is to appropriately balance the induced and autonomous processes throughout these cycles. We also propose that such strategic leadership is the means through which leadership style exerts its influence on corporate longevity. Our findings can be related to organizational research on structural inertia, learning and adaptation, as well as to formal theories of complex adaptive systems. They also contribute to resolving the seeming contradiction between a study of corporations that attributes exceptional long‐term success to leadership style, and the more common proposition that strategy is the determinant of long‐term performance. Copyright © 2007 John Wiley & Sons, Ltd.     

Evolutionary dynamics on infinite strategy spaces

Summary. The study of evolutionary dynamics was so far mainly restricted to finite strategy spaces. In this paper we show that this unsatisfying restriction is unnecessary. We specify a simple condition under which the continuous time replicator dynamics are well defined for the case of infinite strategy spaces. Furthermore, we provide new conditions for the stability of rest points and show that even strict equilibria may be unstable. Finally, we apply this general theory to a number of applications like the Nash demand game, the War of Attrition, linear-quadratic games, the harvest preemption game, and games with mixed strategies. Received: June 25, 1999; revised version: January 31, 2000     

Gibbsian and non-Gibbsian states at Eurandom

We review some of the work on non-Gibbsian states of the last 10 years, emphasizing the developments in which Eurandom played a role.