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A core interest in studies of mutualistic interactions is the 'effectiveness' of mutualists in providing benefits to their partners. In plant-animal mutualisms it is widely accepted that the total effect of a mutualist on its part...
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A core interest in studies of mutualistic interactions is the 'effectiveness' of mutualists in providing benefits to their partners. In plant-animal mutualisms it is widely accepted that the total effect of a mutualist on its partner is estimated as (1) a 'quantity' component multiplied by (2) a 'quality' component, although the meanings of 'effectiveness,' 'quantity,' and 'quality' and which terms are applied to these metrics vary greatly across studies. In addition, a similar quantity x quality = total effect approach has not been applied to other types of mutualisms, although it could be informative. Lastly, when a total effect approach has been applied, it has invariably been from a phytocentric perspective, focussing on the effects of animal mutualists on their plant partner. This lack of a common framework of 'effectiveness' of mutualistic interactions limits generalisation and the development of a broader understanding of the ecology and evolution of mutualisms. In this paper, we propose a general framework and demonstrate its utility by applying it to both partners in five different types of mutualisms: pollination, seed dispersal, plant protection, rhizobial, and mycorrhizal mutualisms. We then briefly discuss the flexibility of the framework, potential limitations, and relationship to other approaches.
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The purpose of this research is focused on equity mutual fund in Indonesia at 2007-2013. From equity mutual fund that active at 2007-2013 this research examined whether selected factors influence the performance of equity mutual f...
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The purpose of this research is focused on equity mutual fund in Indonesia at 2007-2013. From equity mutual fund that active at 2007-2013 this research examined whether selected factors influence the performance of equity mutual fund. Then this research also investigated which equity mutual fund's performance exceeded performance of Indonesia stock index (IHSG). 5 equity mutual funds that exceed Indonesia stock index (IHSG) is panin dana maksima, schroder dana istimewa, pratama saham, batavia dana saham, dan BNP Paribas pesona. This research can provide recommendation for small and medium enterprise to allocate their fund in mutual fund. SMEs usually have a volatile revenue and income stream. In order to reduce the operational risk, SMEs allocates high cash position as a buffer during difficult situation. This paper aims to increase earning from this cash position through investment strategy.
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This paper examines the determinants of cross-sectional variation in post-merger mutual fund performance. Mergers between funds with similar management objectives, as reflected by average portfolio book-to-market ratio, price-earn...
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This paper examines the determinants of cross-sectional variation in post-merger mutual fund performance. Mergers between funds with similar management objectives, as reflected by average portfolio book-to-market ratio, price-earnings ratio, beta and market capitalization values, outperform mergers between funds with dissimilar strategies. This superior performance transcends lower portfolio rebalancing costs which might be realized between merging funds which hold more assets in common. These results suggest that mutual fund mergers create collaborative benefits between funds with similar strategies. We also examine if fund governance structures influence the fund pairing process, testing if stronger fund oversight mitigates pairing mismatches. We find that less independent boards of trustees and boards with higher compensation are related to greater strategic mismatches between funds. These results suggest that more entrenched boards are more tolerant of fund mismatches which benefit the investment company, yet are not in investor's best interests.
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Mutual fund advisers either expense the cost of research and other services or pay for them with soft dollars. This study is the first to use actual soft dollar and total brokerage commission figures for a large number of funds an...
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Mutual fund advisers either expense the cost of research and other services or pay for them with soft dollars. This study is the first to use actual soft dollar and total brokerage commission figures for a large number of funds and to examine how soft dollars are linked to mutual fund governance. Employing a survivorship bias-free sample of actively managed US mutual funds, we find that higher soft dollar and total brokerage commissions are associated with higher advisory fees but not with higher risk-adjusted fund returns. These findings suggest that mutual fund shareholders, on average, do not benefit from the research and the information supplied by third parties such as brokers. We also find that larger and more highly compensated boards are associated with lower advisory fees. Larger boards are also associated with slightly lower turnover. The median tenure of board directors is negatively correlated with soft dollar commissions and turnover, but not correlated with total brokerage commissions or the cost of turning over a portfolio. Higher proportions of directors with a finance background are associated with higher advisory fees, brokerage commissions, and turnover costs. These associations might indicate greater agency costs.
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Although most studies of mutualisms focus on a single partner at a time, host species often associate with multiple mutualist partners simultaneously. Because of potential interactions between mutualists, only studying a single ty...
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Although most studies of mutualisms focus on a single partner at a time, host species often associate with multiple mutualist partners simultaneously. Because of potential interactions between mutualists, only studying a single type of mutualism could lead to a biased perspective of mutualism benefit and how mutualisms may scale-up to affect communities. The legume Chamaecrista fasciculata engages in a resource mutualism with nitrogen-fixing rhizobia and also forms symbiotic interactions with ants by providing nectar in exchange for defense against herbivores. Although they provide very different benefits to the plant, both mutualists receive carbon resources from the plant. As a result, these two mutualists are likely to interact, potentially competing for carbon resources or mutually benefitting each other via their positive effects on plant hosts. In a full-factorial field experiment, we explored how rhizobia and ants influence one another, C. fasciculata fitness, and the associated arthropod community. Ants reduced plant allocation to rhizobia, but ants also increased rhizobia contamination of uninoculated plants, suggesting that ants may disperse rhizobia. In turn, rhizobia increased ant abundances, with ants preferentially tending plants with rhizobia. Chamaecrista fasciculata received substantial fitness benefits from rhizobia; in contrast, associating with ants reduced fitness. Additionally, the mutualists interacted to influence the abundance of other arthropods found on the plants. Rhizobia increased arthropod abundances, likely because more nitrogen-rich leaf tissue was more attractive to arthropod herbivores, but ants negated these increases. As these results illustrate, multiple mutualists may interact, influencing each other's abundance and the abundance of other community members.
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We conduct the first comparative analysis of the financial performance of global water mutual funds with conventional, ecology and natural resources mutual funds. Based on a unique sample of 88 water, 198 ecology, 370 natural reso...
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We conduct the first comparative analysis of the financial performance of global water mutual funds with conventional, ecology and natural resources mutual funds. Based on a unique sample of 88 water, 198 ecology, 370 natural resources, and 7,437 conventional mutual funds covering the 2008-2017 period, we contrast the financial performance of these four different fund types. On average, water mutual funds perform comparably to conventional mutual funds and outperform ecology and natural resources funds. The performance dynamics is linked to the state of the economy, such that the outperformance by water mutual funds is not observed when markets are bearish. Overall, fund risk-adjusted performance is predominantly driven by investor activity, especially with regards to their perception of environmental regulatory risk profiles of funds' constituents.
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Due to its simplicity, efficiency, and efficacy, naive Bayes (NB) has continued to be one of the top 10 algorithms in the data mining and machine learning community. Of numerous approaches to alleviating its conditional independen...
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Due to its simplicity, efficiency, and efficacy, naive Bayes (NB) has continued to be one of the top 10 algorithms in the data mining and machine learning community. Of numerous approaches to alleviating its conditional independence assumption, feature weighting has placed more emphasis on highly predictive features than those that are less predictive. In this paper, we argue that for NB highly predictive features should be highly correlated with the class (maximum mutual relevance), yet uncorrelated with other features (minimum mutual redundancy). Based on this premise, we propose a correlation-based feature weighting (CFW) filter for NB. In CFW, the weight for a feature is a sigmoid transformation of the difference between the feature-class correlation (mutual relevance) and the average feature-feature intercorrelation (average mutual redundancy). Experimental results show that NB with CFW significantly outperforms NB and all the other existing state-of-the-art feature weighting filters used to compare. Compared to feature weighting wrappers for improving NB, the main advantages of CFW are its low computational complexity (no search involved) and the fact that it maintains the simplicity of the final model. Besides, we apply CFW to text classification and have achieved remarkable improvements.
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This article presents an overview of the mutual fund industry in India and the reasons for its poor penetration, which includes lack of objective research. It benchmarks the industry globally, and raises key issues regarding the o...
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This article presents an overview of the mutual fund industry in India and the reasons for its poor penetration, which includes lack of objective research. It benchmarks the industry globally, and raises key issues regarding the ownership and performance of mutual funds, the sensitivity of fund flows to performance, and the importance of regulation to its growth, all of which have been largely under researched in India. It then captures the views of leading practitioners on these and other issues, including the challenges posed by poor financial literacy, the equity culture in the country, and the weakly supportive regulatory environment.
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In this paper, we introduce the concept of mutually best approximation of x, y in D-metric space X with respect to G ? X. Then we consider a special D-metric on a normed space X and introduce the topology generated by this D-metri...
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In this paper, we introduce the concept of mutually best approximation of x, y in D-metric space X with respect to G ? X. Then we consider a special D-metric on a normed space X and introduce the topology generated by this D-metric on X, then generalize some results of best approximation for mutually best approximation.
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Recent studies have assessed the influence of different types of gradients (e.g. altitudinal, latitudinal and temporal, among others) on the structure and function of community-level plant-pollinator webs. Although the importance ...
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Recent studies have assessed the influence of different types of gradients (e.g. altitudinal, latitudinal and temporal, among others) on the structure and function of community-level plant-pollinator webs. Although the importance of humidity as a major driver of species-richness gradients worldwide has been stressed by recent reviews, no studies have been specifically designed to address the influence of precipitation gradients on pollination webs. In the present paper we describe for the first time the turnover of species of plants and their associated flower visitors between eight communities located along a steep precipitation gradient in north-west Patagonia, Argentina. Our results show that: (i) there is a high spatial turnover of plant communities and their associated pollinators; (ii) this turnover is strongly related to precipitation changes across the region; and (iii) the turnover rate is similar for plants and pollinators. Our results support the view that the precipitation gradient is a significant factor associated with the regional turnover of plants and their pollinators in the temperate forests of southern South America.
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