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971.
Children do not choose what to eat based on health issues alone, and the high availability of non‐nutritious food in the environment can be a barrier to the consumption of healthy foods. Brazilian children are consuming processed, savoury, rich in fat, sodium and refined carbohydrates rather than more nutrient‐dense foods. Foods offered in public school meals and those sold in private school canteens in Brazil are subject to regulation, but not the snacks brought from home. This study identified the suggestions of public and private school students about the characteristics that a snack should present in order to be considered both healthy and palatable. A qualitative exploratory study using focus groups was conducted with 128 primary school students aged 7–10 years old. Interviews were transcribed and content analysis was conducted, generating three categories: (1) foods actually consumed during snack breaks; (2) examples of foods considered healthy and/or tasty for consumption during snack breaks; and (3) desired characteristics of a healthy and tasty snack. Foods of high energy density and low nutritional value were mentioned as the most consumed snacks, usually brought from home or purchased within/near the schools. Consumption of meals offered by the National School Meal Program was reported by only one‐third of the public school students. Fruits, natural juices and vegetables were considered healthy foods; sweet‐tasting preparations containing fruits were considered tasty; while fruits and natural fruit juices were considered both healthy and tasty. Sweet‐tasting preparations containing fruits were mentioned as examples of snacks with the desired healthy/tasty characteristics. The disparity between what was actually consumed and what was reported as ideal leads us to question the availability in retail stores of healthy yet palatable foods that meet this population's desires.  相似文献   
972.
Is gold a hedge, defined as a security that is uncorrelated with stocks or bonds on average, or is it a safe haven, defined as a security that is uncorrelated with stocks and bonds in a market crash? We study constant and time‐varying relations between U.S., U.K. and German stock and bond returns and gold returns to investigate gold as a hedge and a safe haven. We find that gold is a hedge against stocks on average and a safe haven in extreme stock market conditions. A portfolio analysis further shows that the safe haven property is short‐lived.  相似文献   
973.
Economists’ faith that variable exchange rates benevolently equilibrate has been empirically disconfirmed. That faith is here tackled at its theoretical core with an exchange rate model that although ultra abstract, includes the undeniable fundamentals of market power and differential goals of central bankers and large-scale private players. It permits a game theoretic analysis under the assumption that all agents maximize their payoffs. The paper then relaxes the assumption of maximising agents, allowing for a more complex and thus realistic second version of the model that is interpretable within SKAT, the Stages of Knowledge Ahead Theory of risk and uncertainty. In an experimental setting, this second version of the model points to: a) the inability of agents in central banks, governments and the private real and financial sectors to operate in maximising ways; b) destructive central bank conflict; and c) the widely discrepant outcomes arising from the dynamics of individual personality differences. The paper’s theoretical and empirical findings thus both point to the merits of a single world currency.  相似文献   
974.
Assuming a symmetric relation between returns and innovations in implied market volatility, Ang, A., Hodrick, R., Xing, Y., and Zhang, X. (2006) find that sensitivities to changes in implied market volatility have a cross‐sectional effect on firm returns. Dennis, P., Mayhew, S., and Stivers, C. (2006), however, find an asymmetric relation between firm‐level returns and implied market volatility innovations. We incorporate this asymmetry into the cross‐sectional relation between sensitivity to volatility innovations and returns. Using both portfolio sorting and firm‐level regressions, we find that sensitivity to VIX innovations is negatively related to returns when volatility is rising, but is unrelated when it is falling. The negative relation is robust to controls for other variables, suggesting only the increase in implied market volatility is a priced risk factor. © 2010 Wiley Periodicals, Inc. Jrl Fut Mark 31:34–54, 2011  相似文献   
975.
976.
Logistics optimization has significantly grown in popularity over the last few decades. Improvements in computing power, modeling software, and the willingness of companies to invest time in the modeling effort have allowed models that were once too unwieldy to solve to optimality to be solved quickly. This has led to a more wide‐spread recognition by logistics managers of the potential advantages of using optimization. The scope of logistics optimization in companies and organizations has expanded to address strategic, tactical, operational, and collaborative decision making. Spreadsheets, an analytical tool familiar to managers, have played a crucial role in the expanded modeling efforts of companies. Although optimization’s role in logistics has grown tremendously, there still are areas that remain to be explored that will allow it to achieve an even larger and more successful role in the management of companies. Additionally, there are some models that are still too large or too complex to currently solve to optimality, despite the advances in computing power and modeling/solving software.  相似文献   
977.
Searching for the best worker, a reliable supply alternative, or the most profitable investment is frequently delegated to an agent. This article develops a theory of delegated search. We show that the principal’s ability to delegate depends on the agent’s luck, her initial resources, and the contract that governs her search. With moral hazard, the optimal contract is characterized by performance deadlines with bonuses for early completion. If performance cannot be specified, the optimal search is implemented by an option‐to‐buy contract for the principal. If performance is partially specified, the optimal contract is a standard pay‐for‐performance arrangement.  相似文献   
978.
Entrepreneurship is commonly held to be a vital force in the US and other economies. Yet, little is known regarding the efficacy of entrepreneurial efforts developed in one country but attempted elsewhere. In response to calls for testable theoretical models, scholars have begun to investigate empirically the attendant phenomena associated with the venture development process. This article describes efforts to test in another nation a nine-stage entrepreneurial process model of venture development derived and validated in the USA. While some development stages appear to exist similarly across borders, others may not be present. Further, the sequence of stages in the US-derived model may differ when compared internationally.  相似文献   
979.
980.
Like the gold standard, price-level targeting (PT) involves not letting past deviations of inflation be bygones; both regimes return the price level (or price of gold) to its target. The experience of suspension of the gold standard in World War I and resumption in the 1920s (for some countries at a different parity) is reviewed. It suggests that, in practice, PT might operate with an escape clause that would allow rebasing of the price target in the face of large shocks. Using a calibrated general equilibrium model, we show that such an escape clause can produce multiple equilibria. For some parameterizations, there is a low credibility equilibrium (with high expectation of a reset) associated with high output volatility and frequent resets. These problems reduce, or reverse, the expectational advantage PT has over inflation targeting.  相似文献   
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