Innovation Dynamics And Endogenous Adjustment In The Telecommunications Industry

Patterned innovation dynamics - investment-mix shifts and inter-organizational alliances -are examined for their roles in facilitating accelelating technical advance in the telecom industry since the mid-1970s. While internal investment shifts favoring R&D and declining rates of capital recovery were ubiquitous across the period, this was especially so for telecom equipment suppliers. Comparative analyses suggest that such innovation investment strategies have been of less benefit to telecom firms than to producers in nearly any other major manufacturing sector. Trends in organizational innovation in the form of alliance fonnation are also reported. The challenges these innovation dynamics pose for neoclassical models are discussed.     

The Economic Convergence Performance of Central and Eastern European Countries

A critical discussion of a comparative growth analysis about Central and Eastern European (CEE) countries is performed. The main conclusion is that there was economic convergence for most CEE accession candidates, but not between them and Western Europe. Results do justify a separation into first and second-wave accession countries, but also undermine differences in Central and Eastern Europe between accession and non-accession countries.This paper critically examines theories and empirical studies for three types of convergence, namely , and club convergence. Each can be in absolute terms or conditional to the long-term equilibrium (steady state) for each country.Empirical results are provided for all types of convergence from 1996 to 2000, both with population-weighted and non-weighted data. The analysis is performed for differently framed country subgroups considering even Western Europe for better comparability. Once absolute convergence is found through a unit root test about a standard deviation time series of cross-sectional income per capita, the regression coefficient for initial income per capita with the average growth over the sample period as dependent variable ( convergence) establishes the speed of this process. The same method applies to the conditional version by using the distance of the income from the corresponding steady state instead of the level of GDP. Then Markov chain probability matrixes (club convergence) provide information about the past behaviour of the whole cross-sectional income distribution over time, but also about intra-mobility of single countries.     

FANUC 0MD数控系统的应用——以XK714数控铣床为例

本文以XK714数控铣床为例,介绍了FANUC 0MD数控系统的构成、各模块功能以及接口信号的含义。     

“Buy Domestic” Campaigns and Optimal Tariffs

This paper attempts to analyze the strategic use of optimal tariffs and to examine the effects of national bias on the optimal trade policy and social welfare in a two-country, two-good, price competition model derived from Neven et al. (1991). The major findings are as follows. (1) If all consumers prefer the domestic good, then buy domestic campaigns will decrease the prohibitive tariff rate and increase local welfare. (2) If at least some consumers prefer the foreign good, but not to a great extent, then buy domestic campaigns will not change the optimal tariff rate, but may improve local welfare. (3) When all consumers greatly prefer the foreign good, then promotion of buy domestic decreases the optimal tariff rate, but it cannot improve social welfare. With this framework, we also prove that buy domestic campaigns serve as a substitute for tariffs with respect to a strategic trade policy.     

On the Mechanics of Economic Convergence

Abstract. The speed at which an economy converges to its steady state is investigated by using a general non-scale R&D-based growth model. To accomplish this task, an analytical decomposition formula for the instantaneous rate of convergence is developed. By applying this decomposition to the model under study, the driving forces behind the convergence process are identified. Two convergence mechanisms are distinguished: the accumulation–decumulation mechanism and the resource–reallocation mechanism. The relative importance of the different convergence mechanisms is assessed using numerical techniques. Moreover, it is shown that the specific shock being considered might be crucial for the instantaneous rate of convergence.     

Implications of state-dependent pricing for dynamic macroeconomic models

State-dependent pricing (SDP) models treat the timing of price changes as a profit-maximizing choice, symmetrically with other decisions of firms. Using quantitative general equilibrium models which incorporate a “generalized (S,s) approach,” we investigate the implications of SDP for topics in two major areas of macroeconomic research, the early 1990s SDP literature and more recent work on persistence mechanisms. First, we show that state-dependent pricing leads to unusual macroeconomic dynamics, which occur because of the timing of price adjustments chosen by firms as in the earlier literature. In particular, we display an example in which output responses peak at about a year, while inflation responses peak at about 2 years after the shock. Second, we examine whether the persistence-enhancing effects of two New Keynesian model features, namely specific factor markets and variable elasticity demand curves, depend importantly on whether pricing is state dependent. In an SDP setting, we provide examples in which specific factor markets perversely work to lower persistence, while variable elasticity demand raises it.     

Interdependence or contagion: A model switching approach with a focus on Latin America

Empirical research analysing contagion has become increasingly fragmented. Different definitions of contagion have resulted in different methods being deployed to analyse financial transmission channels. This paper devises a novel econometric strategy where the nature of interdependencies, magnitude of interdependencies and transmission channels selected for inclusion can change over time. We thus appeal to multiple definitions of contagion, distinguishing between: interdependence, contagion through interdependence and abrupt contagion through changing linkages. Using our approach we analyse different crisis episodes in Latin America. Results generally indicate interdependence not contagion during the currency crises of the 1990s and Argentine crisis of 1998–2002. During the global financial crisis, results indicate abrupt contagion from the US to Argentina and Brazil. Mexico, however, experiences contagion through existing interdependencies with the US. Results also show that macroeconomic and uncertainty channels play a role during different crises not just financial channels. By establishing whether or not different interdependencies and transmission channels are present during different crises our model switching approach provides new insights.     

Estimation and tests for power-transformed and threshold GARCH models

Consider a class of power-transformed and threshold GARCH(p,q)$(p,q)$ (PTTGRACH(p,q)$(p,q)$) model, which is a natural generalization of power-transformed and threshold GARCH(1,1) model in Hwang and Basawa [2004. Stationarity and moment structure for Box–Cox transformed threshold GARCH(1,1) processes. Statistics & Probability Letters 68, 209–220.] and includes the standard GARCH model and many other models as special cases. We first establish the asymptotic normality for quasi-maximum likelihood estimators (QMLE) of the parameters under the condition that the error distribution has finite fourth moment. For the case of heavy-tailed errors, we propose a least absolute deviations estimation (LADE) for PTTGARCH(p,q)$(p,q)$ model, and prove that the LADE is asymptotically normally distributed under very weak moment conditions. This paves the way for a statistical inference based on asymptotic normality for heavy-tailed PTTGARCH(p,q)$(p,q)$ models. As a consequence, we can construct the Wald test for GARCH structure and discuss the order selection problem in heavy-tailed cases. Numerical results show that LADE is more accurate than QMLE for heavy-tailed errors. Furthermore, the theory is applied to the daily returns of the Hong Kong Hang Seng Index, which suggests that asymmetry and nonlinearity could be present in the financial time series and the PTTGARCH model is capable of capturing these characteristics. As for the probabilistic structure of PTTGARCH(p,q)$(p,q)$ model, we give in the appendix a necessary and sufficient condition for the existence of a strictly stationary solution of the model, the existence of the moments and the tail behavior of the strictly stationary solution.     

考虑延迟交货的C2M订单接受决策

以C2M加工装配型制造商在产能约束情形下的订单接受决策问题为研究对象,探讨不同延迟交货率对订单利润的影响。运用约束理论和0-1整数规划法,将企业产能、订单利润、交货期、延迟交货率与订单接受决策相结合,建立了基于产能约束的订单接受决策模型,讨论不同延迟交货率对订单利润的影响;以实现订单利润最大化为目标,通过算例分析对得到的结果进行验证。研究表明,设置适当水平的延迟交货率可以实现订单利润最大化。研究成果可为C2M条件下制造商优化生产管理、完善C2M订单生产决策提供参考。