基于产业链的企业经营指标预测研究及实证分析

客观科学的预测企业主要经济指标是非常重要的,但是比较困难的。采用数学模型是一种有效的科学方法。本文尝试基于产业链,运用计量经济学的方法,使用GDP和行业数据,模拟出数学模型,以此来预测企业的主要经济指标。并以造纸业为例进行实证分析。     

Does interdependency affect firm and industry profitability? an empirical test

Strategy researchers have argued that heterogeneity in firms' practices and profitability within and across industries may derive from industry‐level differences in the extent of interdependencies among firms' activities. Theoretical models have clarified how and why differences in the extent of the interdependencies faced by firms across industries may affect the distributions of firm profits, but the specific predictions from these models have not been empirically tested. In this paper, we present what we believe is the first large scale empirical analysis linking differences in the extent of interdependencies across industries to differences in the distribution of firm profits within and across those industries. We use survey data to measure interdependencies systematically across a wide number of industries, thus addressing the primary obstacle to incorporating interdependencies in larger scale empirical work, and find evidence consistent with the theoretical predictions: average profitability is highest in industries with moderate levels of interdependency; the dispersion of profits among firms is higher in industries with more extensive interdependencies; and industries with more extensive interdependencies have a more positively skewed performance distribution. We find that the effect of interdependencies on average industry profitability is similar in scale to the effect of patent protection and industry growth rates, placing interdependency squarely among the strategy field's central concepts. Copyright © 2009 John Wiley & Sons, Ltd.     

Evolution and challenges of dairy supply chains: Evidence from supermarkets,industries and consumers in Ethiopia

In developing countries the demand for products of animal origin is expected to grow rapidly in the coming years. Using data collected from 200 urban households this study examines the evolution of the dairy market in Ethiopia. In particular, this study suggests that although the Ethiopian dairy market remains extremely thin and volatile, the commercialization of processed dairy products through supermarkets is expanding and is expected to keep doing so in the foreseeable future. Increasing urbanization and corresponding changes in consumer preferences, behaviour and purchasing power are the identified causes for the rise of supermarket-processor dairy chains. This study shows also that emerging dairy chains provide new market opportunities to Ethiopian farmers, but the existence of retail-industrial monopolies and monopsonies jeopardize farmers’ economic benefits to a great extent. The study concludes with some implications for policy and further research.     

What makes countries initiate WTO disputes on food-related issues?

This paper analyses relevant determinants for the probability to initiate a dispute on policy measures under the World Trade Organization (WTO) dispute settlement system. The empirical analysis differs from existing assessments by focusing on agro-food-related disputes and provides a more in-depth analysis of specific country and sectoral characteristics not considered in previous studies. Contrary to recent analyses of overall trade disputes, the results show that some determinants such as legal capacity and monetary means are not statistically significant. Own protectionist behaviour, endured protectionism, and the duration of WTO membership, however, could be identified as relevant determinants with the expected direction of impact.     

Interaction of size,book‐to‐market and momentum effects in Australia

This study seeks to disentangle the effects of size, book‐to‐market and momentum on returns. Initial results show that each characteristic has a role in explaining returns, but that there is interaction between size and momentum, as well as between size and book‐to‐market. Three key findings emerge. First, the size premium is the strongest, particularly in the loser portfolios. Second, the value premium is generally limited to the smallest portfolios. Third, the momentum premium is evident for the large‐ and middle‐sized portfolios, but loser stocks significantly outperform winner stocks in the smallest size portfolio. When these interactions are controlled with multivariate regression, we find a significant negative average relation between size and returns, a significant positive average relation between book‐to‐market and returns, and a significant positive average relation between momentum and returns.     

青岛啤酒物流模式探讨与分析

青岛啤酒招商局物流有限公司（下称青啤招商物流）是＂青啤模式＂的载体。青岛啤酒的物流资产和招商局物流先进的物流管理经验的物流合作模式,被誉为＂青啤模式＂,在国内尚属首创。＂青啤模式＂可以避免国企在物流外包中不可克服的阻力和障碍,在原物流资产和人员持续存在的情况下,实现与专业物流企业双赢的局面,对国内企业特别是国有企业的物流改革有重大示范作用,成为业界和媒体津津乐道的案例。     

The impact of relative residence times on the distribution of heavy drinkers in highly distinct environments

Alcohol consumption is a function of social dynamics, environmental contexts, individuals' preferences and family history. Empirical surveys have focused primarily on identification of risk factors for high-level drinking but have done little to clarify the underlying mechanisms at work. Also, there have been few attempts to apply nonlinear dynamics to the study of these mechanisms and processes at the population level. A simple framework where drinking is modeled as a socially contagious process in low- and high-risk connected environments is introduced. Individuals are classified as light, moderate (assumed mobile), and heavy drinkers. Moderate drinkers provide the link between both environments, that is, they are assumed to be the only individuals drinking in both settings. The focus here is on the effect of moderate drinkers, measured by the proportion of their time spent in “low-” versus “high-” risk drinking environments, on the distribution of drinkers.A simple model within our contact framework predicts that if the relative residence times of moderate drinkers are distributed randomly between low- and high-risk environments then the proportion of heavy drinkers is likely to be higher than expected. However, the full story even in a highly simplified setting is not so simple because “strong” local social mixing tends to increase high-risk drinking on its own. High levels of social interaction between light and moderate drinkers in low-risk environments can diminish the importance of the distribution of relative drinking times on the prevalence of heavy drinking.     

Editorial

An Almost Ideal Demand System (AIDS) was utilized to model the United States demand for domestic and imported tobaccos. The model, which includes equations for domestic flue-cured tobacco, domestic air-cured (burley) tobacco, oriental tobacco, and imported flue-cured and burley tobacco, incorporates the impact of economic factors as well as changes in consumer tastes. In this model homogeneity was rejected under certain conditions, but symmetry could not be rejected. These results suggest that imported flue-cured and burley tobacco, to a limited extent, is a substitute for domestic flue-cured tobacco and is a complement for domestic air-cured tobacco. The trend toward lower average nicotine content of domestic cigarettes is shown to have a detrimenta1 effect on the demand for domestic flue-cured tobacco, but a beneficial impact on domestic air-cured (burley), and imported oriental tobaccos.     

The impact of climate and price risks on agricultural land use and crop management decisions

This article aims to investigate the impacts of climate change and of lower and more volatile crop price levels as currently observed in the European Union (EU) on optimal management decisions, average income and income risks in crop production in Western Switzerland. To this end, a bioeconomic whole-farm model has been developed that non-parametrically combines the crop growth model CropSyst with an economic decision model using a genetic algorithm. The analysis focuses on the farm level, which enables us to integrate a wide set of potential adaptation responses, comprising changes in agricultural land use as well as crop-specific fertilization and irrigation strategies. Furthermore, the farmer's certainty equivalent is employed as objective function, which enables the consideration of not only impacts on average income but also impacts on income variability.The study shows that that the effects of EU crop prices on the optimal management decisions as well as on the farmer's certainty equivalent are much stronger than the effects of climate change. Furthermore, our results indicate that the impacts of income risks on the crop farm's optimal management schemes are of rather low importance. This is due to two major reasons: first, direct payments make up a large percentage of the agricultural income in Switzerland which makes Swiss farmers less vulnerable to market and climate volatility. Second, arable crop farms in Switzerland have by law to cultivate at least four different crops. Due to these diverse cropping systems and high government direct payments risk does neither under climate change, market liberalization nor combinations thereof, play a very decisive role in arable farming in Switzerland.