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1.
We study how natural resource rents affect the risk of internal conflict within countries and how the federal structure of countries influences this relationship. Natural resource abundance may induce excessive rent-seeking and thus increase the risk of internal conflict. Fiscal and political decentralization as an institutional arrangement for rent-sharing and political codetermination of regions within a country may limit the destructive effect of natural resource rents on internal stability. Using cross-country and panel data from more than 90 countries covering the period 1984–2004, we find evidence that natural resource rents indeed increase the risk of internal conflict, but this relationship is significantly mitigated by political decentralization.  相似文献   
2.
Finite mixtures offer a rich class of distributions for modelling of a variety of random phenomena in numerous fields of study. Using the sample interpoint distances (IPDs), we propose the IPD‐test statistic for testing the hypothesis of homogeneity of mixture of multivariate power series distribution or multivariate normal distribution. We derive the distribution of the IPDs that are drawn from a finite mixture of the multivariate power series distribution and multivariate normal distribution. Based on the empirical distribution of the IPDs, we construct a bootstrap test of homogeneity for other multivariate finite mixture models. The IPD test is applied to mixture models for matrix‐valued distributions and a test of homogeneity for Wishart mixture is presented. Numerical comparisons show that IPD test has accurate type I errors and is more powerful in most multivariate cases than the expectation–maximization (EM) test and modified likelihood ratio test.  相似文献   
3.

Warren Buffett has had extraordinary success as an investor, but there is no agreement as to why. Some academic researchers attribute his performance to mere luck. Frazzini et al. (Financ Anal J 74(4):35–55, 2018), concluded that his alpha is due to leveraging safe, high-quality, and cheap stocks. However, there has been no analysis to date of Buffett’s performance from a behavioral perspective. We argue that Buffett’s success is partly due to qualitative and psychological factors, including tenacity, patience, avoidance of overconfidence, organizational culture, and the reputation effect. Using information from shareholder letters, writings, interviews, and speeches by Buffett and his colleague Charlie Munger, we demonstrate how such psychological factors, together with the quantitative findings of Frazzini et al., render a more complete and satisfying explanation of Buffett’s alpha.

  相似文献   
4.
This paper examines the cumulative market reaction to the events related to deferral of internal control audit requirement under the Sarbanes-Oxley Act of 2002 and its elimination under the Dodd-Frank Act of 2010 for nonaccelerated filers (small firms). We document that small firms experienced negative cumulative abnormal returns around these events; and the differences between the cumulative abnormal returns for small firms and the two control groups (accelerated and large accelerated filers) were negative and significant at the 1% level. These results support the notion that market participants value the reliability of financial information irrespective of the firm size. Within the small firms, we find no firm characteristic significantly explains the market reaction to the events considered. That is, all small firms lost market value in reaction to the events that delayed and eliminated their internal control audit requirement.  相似文献   
5.
Motivated by the rising consensus that corporate engagement in climate change actions holds the key for society's transition into environmentally resilient economy, the study examines whether a firm's commitment to climate change action and its carbon risk exposure shape the firm's debt financing policy. Based on insights drawn from signaling, corporate reputation, and agency theories, we develop models that link corporate commitment to climate change actions and a firm's carbon risk exposure with its debt financing decisions. Using data drawn from S&P 500 companies, for years 2015 to 2019, we find a robust evidence that firms that engage in higher levels of commitment to climate change actions issue a higher proportion of debt with longer terms to maturity, even after controlling for their carbon risk exposure. However, we do not find a robust evidence corroborating an association between firms' carbon risk exposure and their debt financing policy. These findings are consistent with arguments that high-commitment firms enjoy positive reputation, better credit rating, and reduced agency and information asymmetry costs, allowing them to gain easier access to long-term debt markets.  相似文献   
6.
Despite extensive literature on green hotel management and sustainability, scant attention has been given on the role of managers to solve environmental related issues. This study's aim is to assess the effects of managers' green knowledge and green transformational leadership on firms' environmental performance with the mediating effect of green creativity. The study analyzes the perceptions of 363 employees in different managerial positions of the hotel industry employing Partial Last Square Structural Equation Modeling. The findings of the study show a positive effect of green knowledge and green transformational leadership on green creativity and green transformational leadership on environmental performance. Furthermore, green creativity is also found to have significant mediating effect between green knowledge and environmental performance, and green transformational leadership and environmental performance relations. The main implication of the current research is that managers' green concerns might help the stakeholders in the hotel industry to respond through appropriate green initiatives for their organizations. Further suggestions for literature and practice are discussed.  相似文献   
7.
Si bien algunos estudios observan que las minorías étnicas urbanas en China perciben salarios más bajos que la mayoría han, otros no constatan la existencia de esa brecha. Para resolver esta contradicción, los autores proponen desglosar las experiencias laborales por grupo étnico minoritario. El análisis de las minorías étnicas sobre un amplio conjunto de datos indica que las «minorías foráneas», como los tibetanos y los grupos túrquicos, sufren una penalización salarial significativa cuando se controlan las covariables, pero no ocurre lo mismo con la totalidad de las minorías. Estas conclusiones son robustas en varias especificaciones y tienen importantes implicaciones teóricas y en materia de políticas.  相似文献   
8.
Here we consider the record data from the two-parameter of bathtub-shaped distribution. First, we develop simplified forms for the single moments, variances and covariance of records. These distributional properties are quite useful in obtaining the best linear unbiased estimators of the location and scale parameters which can be included in the model. The estimation of the unknown shape parameters and prediction of the future unobserved records based on some observed ones are discussed. Frequentist and Bayesian analyses are adopted for conducting the estimation and prediction problems. The likelihood method, moment based method, bootstrap methods as well as the Bayesian sampling techniques are applied for the inference problems. The point predictors and credible intervals of future record values based on an informative set of records can be developed. Monte Carlo simulations are performed to compare the so developed methods and one real data set is analyzed for illustrative purposes.  相似文献   
9.
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   
10.
The computational complexity, huge memory space requirement, and time-consuming nature of frequent pattern mining process are the most important motivations for distribution and parallelization of this mining process. On the other hand, the emergence of distributed computational and operational environments, which causes the production and maintenance of data on different distributed data sources, makes the parallelization and distribution of the knowledge discovery process inevitable. In this paper, a gossip based distributed itemset mining (GDIM) algorithm is proposed to extract frequent itemsets, which are special types of frequent patterns, in a wireless sensor network environment. In this algorithm, local frequent itemsets of each sensor are extracted using a bit-wise horizontal approach (LHPM) from the nodes which are clustered using a leach-based protocol. Heads of clusters exploit a gossip based protocol in order to communicate each other to find the patterns which their global support is equal to or more than the specified support threshold. Experimental results show that the proposed algorithm outperforms the best existing gossip based algorithm in term of execution time.  相似文献   
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