A comparison of MAD and CVaR models with real features

In this paper we consider two different mixed integer linear programming models for solving the single period portfolio selection problem when integer stock units, transaction costs and a cardinality constraint are taken into account. The first model has been formulated by using the maximization of the worst conditional expectation as objective function. The second model is based on the maximization of the safety measure corresponding to the mean absolute deviation. Extensive computational results are provided to compare the financial characteristics of the optimal portfolios selected by the two models on real data from European stock exchange markets. Some simple heuristics are also introduced that provide efficient and effective solutions when an optimal integer solution cannot be found in a reasonable amount of time.     

Public policies,political cleavages and urban space: state infrastructure policies in São Paulo,Brazil, 1975–2000

This article deals with the state policies of urban infrastructure in São Paulo, Brazil, from 1975 to 2000. Working with primary information about the investments made by the state in public works, we discuss a series of arguments present in the urban studies literature about the patterns of state investment in urban spaces and propose an alternative explanation for state action in Brazilian urban spaces in recent decades. We analyze the main elements that have influenced the overall pattern of investments, describe the main characteristics of this policy over time and in each of the municipal governments of the period, as well as develop an evaluation of the spatial distribution of the resources among each of the main social groups in the city.     

Financial constraints and firm dynamics

This study analyzes the effect of financial constraints (FCs) on firm dynamics. We measure FCs with an official credit rating, which captures availability and cost of external resources. We find that FCs undermine average firm growth, induce anti-correlation in growth patterns and reduce the dependence of growth volatility on size. FCs are also associated with higher volatility and asymmetries in growth shock distributions, preventing young fast-growing firms especially from seizing attractive growth opportunities and further deteriorating the growth prospects of already slow-growing firms, particularly if old. The sub-diffusive nature of the growth process of constrained firms is compatible with the distinctive properties of their size distribution.     

Selection in asset markets: the good, the bad, and the unknown

In this paper, we use a series of simple examples to illustrate how wealth-driven selection works in a market for Arrow securities. Our analysis delivers both a good and a bad message. The good message is that, when traders invest constant fractions of their wealth in each asset and have equal consumption rates, markets are informationally efficient: the best informed agent is rewarded and asset prices eventually reflect this information. However, and this is the bad message, when asset demands are not constant fractions of wealth but dependent upon prices, markets might behave sub-optimally. In this case, asymptotic prices depend on preferences and beliefs of the whole ecology of traders and do not, in general, reflect the best available information. We show that the key difference between the two cases lies in the local, i.e. price dependent, versus global nature of wealth-driven selection.     

Innovation and spillovers in regions: Evidence from European patent data

This paper estimates the effect of research externalities in generating innovation. We use R&D and patent data for European Regions in the 1977-1995 period. We find that spillovers are very localized and exist only within a distance of . The estimates are robust to simultaneity, omitted variable bias, different specifications of distance functions, country and border effects. However the size of these spillovers is small. Doubling R&D spending in a region would increase the output of new ideas in other regions within only by 2-3%, while it would increase the innovation of the region itself by 80-90%.     

Common Properties and Sectoral Specificities in the Dynamics of U.S. Manufacturing Companies

The size distribution and growth rate dynamics of U.S. companieshave been extensively studied by many authors. In this paper,using the COMPUSTAT database, we extend the analysis todisaggregated data, studying 15 sectors of the U.S.manufacturing industry. The sectoral investigation reveals thepresence of general statistical properties that can be consideredvalid across all the studied sectors. In particular, theprobability density of firms growth rates invariably displays acharacteristic tent shape and the relation between the size of afirm and the variance of its rates of growth is characterized, indifferent sectors, by very similar scaling relations. Thepresence of characteristics that are robust and sectoral invarianthints at the existence of generic statistical properties shapingthe dynamic of firms across the whole industry.     

中国生物燃料需求与巴西乙醇

中国gdp快速增长的同时带来严重的大气污染,因此中国政府正在寻求一种更加环保的可再生绿色燃料来满足国内的运输需求。生物燃料是一种从生长过程中吸收co2的植物中提取出来的新型燃料,尽管中国国内并没有足够的农用土地来生产满足其未来消费需求的生物燃料,但是选择生物燃料仍然不失为污染问题的部分解决方法。由于巴西从甘蔗中提取的乙醇比其他国家从谷物中提取的乙醇便宜且排放更少的温室气体,因此从巴西进口乙醇可以说是中国政府最好的选择。加上巴西不但在乙醇工业部门有着其特殊的技术,而且拥有大量的劳动力,丰富的水源和闲置的农业用地,这些条件足以为中国额外生产85亿升的乙醇来满足中国到2020年对乙醇的需求量。     

Consumption Responses to a Large Shock to Financial Wealth: Evidence from Italy

We estimate marginal propensities to consume from wealth shocks. We exploit large asset-price shocks in 2007–2008 and household-level panel data to implement instrumental variables. A fall of one euro in risky financial wealth resulted in cuts to annual total (non-durable) consumption of 8.5–9 (5.5–5.7) cents, with small effects on food spending. Effects seem stronger for lower-wealth or indebted households, but significant responses from wealthier households and those without mortgages are important for our baseline results. Counterfactuals indicate financial-wealth effects were relatively important for consumption falls in Italy in 2007–2008. The estimated effects are consistent with a simulated life-cycle model capturing the wealth shock.     

CEOs' reputation,quality management and environmental innovation: The roles of stakeholder pressure and resource commitment

In this paper, we examine how and when chief executive officers' (CEOs') reputation enhances environmental innovation by considering quality management as a mediating mechanism of this relationship. In addition, we introduce stakeholder pressures (primary and secondary stakeholder pressures) as important contingencies of the relationship between CEOs' reputation and quality management. Moreover, we test the moderating role of resource commitment on the quality management‐environmental innovation relationship. We test our research model using data from a manufacturing industry sample of 217 firms from Ghana. We find that quality management mediates the relationship between reputation and environmental innovation. Moreover, the relationship between CEOs' reputation and quality management is amplified when levels of both primary and secondary stakeholder pressures are greater. Finally, our findings show that the effect of quality management on environmental innovation is enhanced when resource commitment is greater. Implications for theory and practice are discussed.     

Perceived Differences: Chinese and Russian Farmers on Business,Law, Management,and Environment

The People's Republic of China has been following a strategy for several decades to encourage its enterprises to invest overseas. Since the liberalization of the Sino-Soviet border in the 1990s, Chinese farmers have been actively engaged in the economy of the Russian Far East (RFE). This article examines Chinese and Russian public relations messages broadcast by media about Chinese-Russian agricultural cooperation that use different arguments, methods of reasoning, and points of view. There is a clash of different national management methods. Legislation applying to Chinese working in Russia has been erratic and unstable, and that makes cooperation more challenging. The concepts of environmental protection and obedience to the law are understood differently by Russians and by Chinese. Cross-cultural management differences affect the way people on both sides interpret institutions, interactions, and the ability to trust third parties. There are different values and priorities expressed by Russians and by Chinese when it comes to development of rural areas in the RFE.