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161.
This article investigates the impact of foreign competition from China on employment and wages in four U.S.-Mexico Border counties: Santa Cruz, Arizona; San Diego, California; El Paso, Texas; and Webb, Texas. Using disaggregated industry-level data between 1992 and 2006, we find that increased trade with China is associated with significantly lower county-industry employment and wages. In contrast, and as expected, increased imports from Mexico are positively related to increased employment and wages in U.S.-Mexico border counties. The results indicate that the U.S.-Mexico supply-chain relationship related to the maquiladora industry is significantly affected by Chinese competition. Implications for policy include an increased focus on federal programs that are intended to diversify the border economy . ( JEL F13, F43, F23)  相似文献   
162.
Scenarios are claimed to support strategic decision makers. They are especially effective in dealing with uncertainties. This paper addresses some drawbacks of the conventional scenario method, which is especially directed at handling these uncertainties, and indicates possible avenues for methodological adaptations. We take the approach, which rests in the Shell tradition, as exemplary for our discussion on the mainstream scenario methodology. This approach has some limitations when it comes to dealing with simultaneous trends and countertrends, and trends or clusters of trends that are not thought of beforehand, especially the methodological requirements of causality and consistency, which might be limiting factors in this respect. This paper indicates alternative ways for scenario construction. It discusses the use of either recombinant scenarios, context scenarios, or inconsistent scenarios and/or combinations of these scenarios. These options explicitly incorporate the notion of ‘paradoxical trend’ as the codriver of future developments into the methodology.  相似文献   
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A.  B.  K.  V.  A.  P.  I.  S.  E. 《Technological Forecasting and Social Change》2007,74(7):980-1029
We report here spatially explicit scenario interpretations for population and economic activity (GDP) for the time period 1990 to 2100 based on three scenarios (A2, B1, and B2) from the IPCC Special Report on Emissions Scenarios (SRES). At the highest degree of spatial detail, the scenario indicators are calculated at a 0.5 by 0.5 degree resolution. All three scenarios follow the qualitative scenario characteristics, as outlined in the original SRES scenarios. Two scenarios (B1 and B2) also follow (with minor adjustments due to scenario improvements) the original SRES quantifications at the level of 4 and 11 world regions respectively. The quantification of the original SRES A2 scenario has been revised to reflect recent changing perceptions on the demographic outlook of world population growth. In this revised “high population growth” scenario, A2r world population reaches some 12 billion by 2100 (as opposed to some 15 billion in the original SRES A2 scenario) and is characterized by a “delayed fertility transition” that is also mirrored in a delayed (economic) development catch-up, resulting in an initially stagnating and subsequently only very slow reduction in income disparities. The spatially explicit scenario interpretation proceeds via two steps. Through a combination of decomposition and optimization methods, world regional scenario results are first disaggregated to the level of 185 countries. In a subsequent second step, national results are further disaggregated to a grid cell level, taking urbanization and regional (rural–urban) income disparities explicitly into account. A distinguishing feature of the spatially explicit scenario results reported here is that both methodologies, as well as numerical assumptions underlying the “downscaling” exercise, are scenario-dependent, leading to distinctly different spatial patterns of population and economic activities across the three scenarios examined.  相似文献   
166.
This paper assesses to what extent differences in the characteristics of individuals (micro‐level perspective) and country‐specific factors (macro‐level perspective) can explain country differences with respect to material deprivation levels. Thus, our work aims to simultaneously consider the macro dimension and the predominantly individually‐oriented study field of material deprivation using multilevel techniques. We make use of the European Union Statistics on Income and Living Conditions. Our results show that country‐specific factors seem to be much more relevant than individual effects in explaining country differences in material deprivation. We estimate that the introduction of country‐specific factors reduces the proportion of total variance due to between‐country differences in deprivation by 72.7 percent, while individual‐level variables reduce this proportion by only 9.4 percent. We also show, through interaction variables, that the effect of sociodemographic characteristics can be shaped by institutional and structural factors, especially by the level of GDP.  相似文献   
167.
The propensity of the forecasts of sell-side financial analysts to converge (or diverge) is a function of their exogenous and endogenous selective attention and overconfidence. When returns are negative, the endogenous form of selective attention—a static measure of analysts’ goal-driven attention at a particular point in time—has a positive association with convergence. The exogenous form of selective attention—a relatively involuntary dynamic process of exogenous attentional shift driven by external changes in the market over time—is associated with a tendency for forecasts to diverge.  相似文献   
168.
Abstract

The following situation is considered. A fixed number (= n) or sequence of independent trials T 1 T 2,…, T n is given, and in each of these an event E mayor may not occur, It is further observed that the event E occurs a total of k times amongst the n trials T i , (i = l,…, n). It is then required to test the hypothesis H 0 that the probability of the occurrence of E is constant from trial to trial, i.e. H 0 is the hypothesis: p 1 = p 2 = ? = p n = p, if p n (i = 1, …, n) represents the probability that E occurs on the ith trial.  相似文献   
169.
This study shows that firms in the pharmaceutical industry experience decreasing returns to scale in R & D as the level of R & D expenditures rises. The paper presents the results of our study of the innovative output of 16 pharmaceutical firms over a 19 year period. Given the strong correlation between R & D budgets and firm size, our study suggests the wave of mergers in the industry may yield less innovative productivity than managers expect.  相似文献   
170.
This paper is devoted to studying optimal designs for estimating an extremal point of a multivariate quadratic regression model in the unit hyperball. The problem of estimating an extremal point is reduced to that of estimating certain parameters of a corresponding nonlinear (in parameters) regression model. For this reduced problem truncated locally D-optimal designs are found in an explicit form. The result is a generalization of the results of Fedorov and Müller (1997) for onedimensional quadratic regression function in the unit segment. Received February 2002  相似文献   
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