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This paper proposes an approach to the intraday analysis of diversified world stock accumulation indices. The growth optimal portfolio (GOP) is used as reference unit or benchmark in a continuous financial market model. Diversified portfolios, covering the world stock market, are constructed and shown to approximate the GOP, providing the basis for a range of financial applications. The normalized GOP is modeled as a time transformed square root process of dimension four. Its dynamics are empirically verified for several world stock indices. Furthermore, the evolution of the transformed time is modeled as the integral over a rapidly evolving mean-reverting market activity process with deterministic volatility. The empirical findings suggest a rather simple and robust model for a world stock index that reflects the historical evolution, by using only a few readily observable parameters. Mathematics Subject Classification: (1991) primary 90A12, secondary 60G30,62P20 JEL Classification: G10, G13  相似文献   
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Protected areas are key to the conservation of global biodiversity and ecosystem services; however, their success is contingent upon adequate funding. One possibility to increase funding for park management is to “sell” a wider suite of ecosystem services “produced” by protected areas, such as carbon sequestration. We conducted 420 tourist surveys to analyze willingness to pay (WTP) for ecosystem service benefits via a conservation fee in the Tambopata National Reserve in Peru. We also interviewed eight tour operators about their perceptions of the proposed fee. The average stated WTP was 15 USD. Sixty-six percent of tourists stated they would pay 10 USD or more, which, if actually paid, would have resulted in 318,000 USD for park management in 2015. Most respondents stated they would pay an additional fee if it supported biodiversity conservation or local ecosystem services, such as water, but less than 10% of tourists were motivated by carbon sequestration as a reason to pay the fee. Most tour operators supported the additional fee. Our findings suggest that tourists are willing to pay higher fees to support conservation but that interest in paying for additional ecosystem services from parks may not extend to global and intangible benefits such as carbon sequestration.  相似文献   
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As restaurants are the primary hospitality business represented on flash-sale sites, this study examined motivations of restaurant managers when choosing whether to utilize the promotional mediums of flash-sales. Interviews were administered as a measurement instrument. Results demonstrated restaurants which have employed flash-sales are weary of the likelihood of success and believe the flash-sales brought in established customers. Non-users indicated hesitation towards adoption of flash-sales related to low profit margins per item in their operation and the percentage split of the sale price between the firm and flash-sale provider. Findings provide keen foundational insight into the flashsale phenomenon.  相似文献   
15.
Young men are far less likely than women to attend university across most OECD countries. I use data from the Youth in Transition Survey (YITS) to investigate this issue in the Canadian context, focusing on how parents might influence this gender gap. In particular, my goal is to isolate the incremental effect of parents’ valuations of education during the teenage years, holding constant the stock of skills acquired up to that point. To estimate this effect, I use a factor model based on a framework developed by Foley et al. (2014). My results confirm the importance of skills in determining the gender gap in university attendance. I also find that differences in the distribution of parental valuations of education account for 22% of the gender gap in the YITS data, pointing toward an important role that parents play, not accounted for in prior work.  相似文献   
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The purpose of this article is to investigate whether place is emerging in practice as a critical dimension in the development of Canadian rural regions. Recently, Jones and Paasi set regional researchers the task of better understanding how regions ‘become'. In researching this question, we are particularly interested in the definition and expression of place‐based identity as a mobilizing force for regionalism. Our findings suggest that, while identity plays a critical role in fostering regional development processes, it is either too emergent or actively resisted within our research sites to be a significant force for place‐based regional development.  相似文献   
17.
This paper reports on a study which explored the customer perspective on their roles in SST encounters in a tourism context, through the theoretical lens of service-dominant logic. The study employed short qualitative interviews with airline passengers at an international airport. The findings suggest that customers can assume six roles in an SST encounter which can be viewed as either positive or negative in terms of value creation. Therefore, a key contribution of this paper is the development of a role–experience continuum which depicts the variations in customer experiences of value creation in a tourism context.  相似文献   
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This study assesses the potential impact of rising world food prices on the welfare of Ugandan households. While Uganda experienced sharply higher food prices in 2008, as a landlocked, food‐exporting country the causes of those price changes were mainly regional and indirect rather than directly transmitted from global markets. Using trade volumes, food prices, and household survey data we describe how Uganda, unlike some other countries, is partially shielded from direct impacts of global food price movements. Although the majority of Ugandans are net food buyers, the adverse impact at household‐level of rising global prices is moderated by the relatively large quantity and range of staples consumed that come from home production. Moreover, several of these are not widely traded. Some population groups in Uganda are vulnerable to rising food prices, however, primarily those for whom maize is an important staple, including those dependent upon humanitarian relief and the urban poor. Only a relatively small group of Ugandan households will benefit directly and immediately from rising food prices—the significant net sellers of food crops constituting between 12% and 27% of the population. In this assessment we do not estimate the level and extent of wider second round effects from these higher prices.  相似文献   
20.
The mechanisms used to deliver agricultural beneficial management practices (BMPs) can influence the performance of these policies. Research has suggested that agri‐environmental instruments targeted based on specific economic or environmental characteristics can improve policy performance. Using a case study approach, we evaluate the relative performance of different mechanisms to target subsidized water retention pond BMPs to reduce phosphorus (P) runoff in an agriculture dominated subwatershed within the Lake Winnipeg watershed in southern Manitoba. The water retention pond BMPs were targeted based on estimated establishment costs (cost targeting), total phosphorus removal from surface water (benefit targeting), and pond‐specific benefit–cost ratios. The targeting was simulated using predictions of retention pond‐specific P removal from an adapted hydrology model and site‐specific pond construction and land opportunity costs assembled in a geographic information system database. Targeting of water retention pond BMPs has an impact on the cost effectiveness of the policy delivery with benefit–cost targeting being the most cost‐effective approach. Water retention ponds providing higher P removal at lower cost were smaller in size and on land previously used for the production of lower value crops. Le ciblage économique des pratiques de gestion bénéfiques en agriculture pour remédier au ruissellement du phosphore au Manitoba Les mécanismes utilisés pour livrer des pratiques de gestion bénéfiques (PGB) peuvent influencer la performance de ces politiques. Des études suggèrent que le ciblage d'instruments agroenvironnementaux basé sur des caractéristiques économiques ou environnementales précises peut améliorer la performance des politiques. Au moyen d'études de cas, nous évaluons la performance relative de divers mécanismes pour cibler les PGB des bassins de rétention d'eau subventionnés pour réduire le ruissellement de phosphore (P) dans un sous‐bassin du bassin du Lac Winnipeg au sud du Manitoba. Les PGB du bassin de rétention des eaux ont été ciblées en fonction des coûts estimés d'établissement (ciblage des coûts), de l′élimination totale du phosphore de la surface de l'eau (ciblage des bénéfices), et des ratios avantages‐coûts liés au bassin. Le ciblage fut simulé au moyen de prédictions du taux de suppression de P spécifique à chaque bassin de rétention obtenues à partir d'une adaptation d'un modèle hydrologique et d'une base de données d'un système d'information géographique (SIG) contenant les sites de chaque bassin de rétention et le coût d'opportunité du terrain. Le ciblage des PGB des bassins de rétention d'eau a un impact sur la rentabilité de la mise en ?uvre de politiques, le ciblage coût‐avantages étant l'approche la plus rentable. Les bassins de rétention d'eau ayant le plus haut taux d'élimination de P à moindre coût s'avéraient plus petits et sur des terrains ayant servi, auparavant, à la production de cultures de moindre valeur.  相似文献   
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