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Biogeographic and diversification patterns of Neotropical Troidini butterflies (Papilionidae) support a museum model of diversity dynamics for Amazonia

Condamine, Fabien L.; Silva-Brandao, Karina L.; Kergoat, Gael J.; Sperling, Felix A. H.
Fonte: BIOMED CENTRAL LTD; LONDON Publicador: BIOMED CENTRAL LTD; LONDON
Tipo: Artigo de Revista Científica
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Background: The temporal and geographical diversification of Neotropical insects remains poorly understood because of the complex changes in geological and climatic conditions that occurred during the Cenozoic. To better understand extant patterns in Neotropical biodiversity, we investigated the evolutionary history of three Neotropical swallowtail Troidini genera (Papilionidae). First, DNA-based species delimitation analyses were conducted to assess species boundaries within Neotropical Troidini using an enlarged fragment of the standard barcode gene. Molecularly delineated species were then used to infer a time-calibrated species-level phylogeny based on a three-gene dataset and Bayesian dating analyses. The corresponding chronogram was used to explore their temporal and geographical diversification through distinct likelihood-based methods. Results: The phylogeny for Neotropical Troidini was well resolved and strongly supported. Molecular dating and biogeographic analyses indicate that the extant lineages of Neotropical Troidini have a late Eocene (33-42 Ma) origin in North America. Two independent lineages (Battus and Euryades + Parides) reached South America via the GAARlandia temporary connection, and later became extinct in North America. They only began substantive diversification during the early Miocene in Amazonia. Macroevolutionary analysis supports the "museum model" of diversification...

A seleção natural e a estrutura, dinâmica e diversificação de assembleias de espécies mutualistas; Natural selection and the structure, dynamics, and diversification of mutualistic assemblages

Raimundo, Rafael Luís Galdini
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 16/04/2015 Português
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A adaptação e a diversificação em sistemas multiespecíficos são crescentemente reconhecidas como processos relevantes para a compreensão da biodiversidade. Nosso objetivo foi investigar como a seleção natural relacionada a interações ecológicas influencia a estrutura, dinâmica e diversificação de assembleias mutualistas. Primeiro, modelamos como mutualismo e competição intraespecífica geram regimes seletivos antagônicos que definem padrões de diversificação. Nossos modelos preveem que em mutualismos de baixa intimidade, nos quais cada organismo têm muitos parceiros individuais, fenótipos extremos têm interações mutualísticas desajustadas em relação à complementaridade de traços, contrabalanceando efeitos diversificadores da competição intraespecífica e restringindo a especiação. Em sistemas de alta intimidade, nos quais mutualismos têm maior impacto adaptativo e cada organismo têm poucos parceiros, tal seleção estabilizadora imposta por mutualismos é reduzida, favorecendo a diversificação. Entretanto, mutualismos de baixa intimidade são mais ricos que mutualismos íntimos na natureza. Sob baixa intimidade de interações, adições de espécies não-aparentadas envolvidas em dinâmicas de convergência constituem explicação plausível para essa discrepância. Em sistemas de alta intimidade...

Revenue diversification in higher education: the case of Portugal; Diversificação de financiamento no ensino superior: o caso de Portugal

Antunes, Tatyana Yuryevna Koryakina
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Tese de Doutorado
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Socio-economic changes, alterations in societal expectations and new public policies have put pressures on higher education public funding, bringing the issue of funding diversification to the forefront. Income diversification, namely, generation of funds from private, as well as from competitive public sources, has become increasingly important in European higher education due to a complex financial environment and perceived deficit of innovation transfer. Although there are numerous studies about changes in national funding systems and allocation mechanisms, few have focused on diversification of funding sources, especially in the European context, making Portugal no exception. Thus, this study aims at exploring income diversification at the institutional level and its influence on the internal organisational structures. For this purpose two Portuguese public universities were chosen as case studies. The empirical material was collected through semi-structured interviews with top management and middle management of each university and through documentary analysis. Data analysis demonstrated that both universities are in the process of institutionalizing and formalising practices of income diversification, notably by getting more professional in how they are dealing with external stakeholders...

Internationalization and diversification strategies of agricultural cooperatives: a quantitative study of the agricultural cooperatives in the state of Parana

Ritossa,Claudia Monica; Bulgacov,Sergio
Fonte: ANPAD - Associação Nacional de Pós-Graduação e Pesquisa em Administração Publicador: ANPAD - Associação Nacional de Pós-Graduação e Pesquisa em Administração
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2009 Português
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This study investigates the impact of internationalization on the results achieved by agricultural cooperatives in the State of Parana, at the same time examining strategies for diversification of markets as well as diversification of products aimed exclusively at international markets. Of the 28 cooperatives to be included in the study, 67.9% returned valid structured questionnaires. The collected data was submitted to non-parametric statistical analysis. Key findings suggest the following: external markets are served by indirect and direct exports; product diversification strategies are motivated by the creation of revenue alternatives to members and by the reduction of risks associated to agricultural business; diversification strategies are conceived to develop new business in accordance with market demand and to expand customized products from the existing portfolio; the formation of strategic alliances prioritizes access to distribution channels abroad; internationalization and diversification strategies produce positive results both from an economic and a social perspective.

A diversificação das atividades nas cooperativas agropecuárias no norte gaúcho; Diversification of activities in agricultural cooperatives in the Northern of Rio Grande do Sul

Fonte: Organizações Rurais & Agroindustriais Publicador: Organizações Rurais & Agroindustriais
Tipo: Artigo de Revista Científica Formato: application/pdf
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Agricultural cooperatives are considered organizations that contribute to the socioeconomic development of the region in which they are located. The action form of the cooperatives, as focus on business diversification, can contribute to the generation of a stronger and more effective rural development. This study aims to demonstrate the diversification existing in the agricultural cooperatives from the Northern of Rio Grande do Sul state. The central objective is to identify and analyze the diversification types based on activities performed by agricultural cooperatives. The theoretical framework for data analysis takes into account the types of diversification used by the cooperatives, especially the concentric and the conglomerate ones. In concentric, new activities are carried out using the same set of technologies already dominated by the cooperative, while in conglomerate new activities are fulfilled but distinct from the usual activities of the cooperative. This study was conducted in three Rio Grande do Sul regions, through the application of a questionnaire on single agricultural cooperatives, affiliated to the Federation of Agricultural Cooperatives of Rio Grande do Sul (FECOAGRO). The results indicate that cooperatives diversify its internal activities offering to the members and community various services: connected to consumption...

Importance of the HSP90 molecular chaperoning pathway for antibody diversification by determining AID stability

Orthwein, Alexandre
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
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La protéine AID (déaminase induite par l’activation) joue un rôle central dans la réponse immunitaire adaptative. En désaminant des désoxycytidines en désoxyuridines au niveau des gènes immunoglobulines, elle initie l’hypermutation somatique (SHM), la conversion génique (iGC) et la commutation isotypique (CSR). Elle est essentielle à une réponse humorale efficace en contribuant à la maturation de l’affinité des anticorps et au changement de classe isotypique. Cependant, son activité mutagénique peut être oncogénique et causer une instabilité génomique propice au développement de cancers et de maladies autoimmunes. Il est donc critique de réguler AID, en particulier ses niveaux protéiques, pour générer une réponse immunitaire efficace tout en minimisant les risques de cancer et d’autoimmunité. Un élément de régulation est le fait qu’AID transite du cytoplasme vers le noyau mais reste majoritairement cytoplasmique à l’équilibre. AID est par ailleurs plus stable dans le cytoplasme que dans le noyau, ce qui contribue à réduire sa présence à proximité de l’ADN. Le but de cette thèse était d’identifier de nouveaux partenaires et déterminants d’AID régulant sa stabilité et ses fonctions biologiques. Dans un premier temps...

Patterns of Export Diversification in Developing Countries : Intensive and Extensive Margins

Amurgo-Pacheco, Alberto; Pierola, Martha Denisse
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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This paper uses highly disaggregated trade data to investigate geographic and product diversification patterns across a group of developing nations for the period from 1990 to 2005. The econometric investigation shows that the gravity equation fits the observed differences in diversification across nations. The analysis shows that exports at the intensive margin account for the most important share of overall trade growth. At the extensive margin, geographic diversification is more important than product diversification, especially for developing countries. Taking part in free trade agreements, thereby reducing trade costs, and trading with countries in the North are also found to have positive impacts on export diversification for developing countries.

Diversification, Innovation, and Imitation inside the Global Technological Frontier

Klinger, Bailey; Lederman, Daniel
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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Recent research highlights the relationship between economic development and productive diversification, which may be hindered by market failures. After identifying stages of diversification in disaggregated export data, the authors develop a metric for the flows of export "discoveries," or inside-the-frontier innovations in developing countries. They then explore the empirical relationship between economic development and (1) inside-the-frontier-innovation as reflected by the introduction of new export products, (2) export diversification measured by an index of export-revenue concentration, and (3) on-the-frontier innovation as reflected in patents. The data suggest, unsurprisingly, that inside-the-frontier innovation is more common among poor countries than among industrial economies. Overall export diversification increases at low levels of development but declines with development after a high-income point, whereas patenting activity rises exponentially with development. The data also suggest that the relationship between the frequency of export discoveries and economic development is not due to changes in the industrial composition of exports. The authors use a simple model of innovation and imitation to test the hypothesis that the threat of imitation inhibits the discovery of new exports. Econometric evidence suggests that the frequency of export discoveries across countries rises with the returns of export activities (proxied by exogenous export growth during the sample period)...

Managing Openness and Volatility : The Role of Export Diversification

Haddad, Mona; Lim, Jamus Jerome; Saborowski, Christian
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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As developing countries look to embrace an outward-oriented growth strategy, some may be concerned about the possibility that increased openness will be accompanied by increased volatility. However, although a more open economy may face increased volatility in its terms of trade, openness confers diversification benefits. In this note, authors argue that export diversification is a key mitigating factor for the total effect of openness on volatility. More specifically, authors show that most developing countries fall on the "good" side of a diversification threshold, where they are likely to experience less volatility as they pursue a strategy of greater openness.

Latent Trade Diversification and Its Relevance for Macroeconomic Stability

Lederman, Daniel; Pienknagura, Samuel; Rojas, Diego
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Trabalho em Andamento
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Traditional measures of trade diversification only take into account contemporaneous export baskets. These measures fail to capture a country’s ability to respond to shocks by allocating factors of production into activities for which it has already paid the fixed costs associated with exporting. This paper corrects for the shortcoming of traditional measures of diversification by introducing a novel measure of trade diversification—latent diversification—and proposes a proxy to measure latent diversification, which is calculated by taking into account the entire history of a country’s exports. The paper shows that the observed gaps between traditional measures of diversification and the proposed proxy of latent diversification are sizeable; countries hold latent export baskets that are, on average, three times as large as their average contemporaneous export basket, and these gaps are largest for poor and small countries. Moreover, latent diversification is an important determinant of volatility—more diversified latent export baskets are associated with lower terms of trade volatility and...

Assessing the Impact of Business Group Diversification on the Internationalization of their Affiliates: The Case of Latin American Firms

Borda, Armando J
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
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This dissertation explored the capacity of business group diversification to generate value to their affiliates in an institutional environment characterized by the adoption of structural pro-market reforms. In particular, the three empirical essays explored the impact of business group diversification on the internationalization process of their affiliates. The first essay examined the direct effect of business group diversification on firm performance and its moderating effect on the multinationality-performance relationship. It further explored whether such moderating effect varies depending upon whether the focal affiliate is a manufacturing or service firm. The findings suggested that the benefits of business group diversification on firm performance have a threshold, that those benefits are significant at earlier stages of internationalization and that these benefits are stronger for service firms. The second essay studied the capacity of business group diversification to ameliorate the negative effects of the added complexity faced by its affiliates when they internationalized. The essay explored this capacity in different dimensions of international complexity. The results indicated that business group diversification effectively ameliorated the effects of the added international complexity. This positive effect is stronger in the institutional voids rather than the societal complexity dimension. In the former dimension...

Corporate diversification and R&D intensity dynamics

Alonso-Borrego, César; Forcadell, Francisco Javier
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: info:eu-repo/semantics/workingPaper; info:eu-repo/semantics/workingPaper Formato: application/pdf
Publicado em /12/2007 Português
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We study the dynamic bidirectional relationship between firm R&D intensity and corporate diversification, using longitudinal data of Spanish manufacturing companies. Our empirical approach takes into account the censored nature of the dependent variables and the existence of firm-specific unobserved heterogeneity. Whereas we find a positive linear effect of R&D intensity on related diversification, the evidence about the effect of related diversification on R&D intensity takes the form of an inverted U. Hence, the effect of related diversification on R&D intensity is positive but marginally decreasing for moderate levels of related diversification, but such effect can turn out negative for high levels of related diversification. Additionally, the consequences of the dynamic relation are that the effects are substantially larger in the long-run than in the short-run.

Related diversification and R&D intensity dynamics

Alonso-Borrego, César; Forcadell, Francisco Javier
Fonte: Elsevier Publicador: Elsevier
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/article Formato: application/pdf
Publicado em /04/2010 Português
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Using longitudinal data of Spanish manufacturing companies, we study the dynamic, bidirectional relationship between firm research and development (R&D) intensity and corporate diversification in an organic growth setting. Our empirical approach accounts for the different sources of endogeneity. Although we find a positive linear effect of R&D intensity on related diversification, the effect of related diversification on R&D intensity assumes the form of an inverted U. Thus, the effect of related diversification on R&D intensity is positive, but marginally decreases for moderate levels of related diversification. Such an effect can become negative, however, for high levels of related diversification. Additionally, as a consequence of dynamics, the effects after one year are substantially lower than the overall effects that occur over several years.; Both authors acknowledge financial support from the Spanish Ministry of Science and Innovation, Grants No. ECO2009-11165 and ECO2009-10358

Natural Resource Abundance, Growth and Diversification in MENA : The Effects of Natural Resources and the Role of Policies

Diop, Ndiame; Marotta, Daniela; de Melo, Jaime
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Brief; Publications & Research
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The Middle East and North Africa (MENA) region is one of the richest in the world in terms of natural resources. It holds more than 60 percent of the world's proven oil reserves, mostly located in the Gulf region, and nearly half of global gas reserves. Not surprisingly, oil represents close to 85 percent of the merchandise exports of the region, making it highly susceptible to fluctuations in international prices. A long strand of economic literature suggests that such dependence may hurt a country's growth prospects and job creation by reducing the scope for economic diversification. A forthcoming WB publication investigates how MENA can overcome this challenge and encourage greater economic diversification. The study examines the pattern of structural transformation in MENA and explores the role of natural resources and macroeconomic policies in driving the current (limited) diversification outcomes. The authors explore analytical questions, such as: (i) the impact of the real exchange rate on manufacturing and tradable services competitiveness in MENA; (ii) the role of fiscal policy in supporting diversification; (iii) how 'weak links' (input sectors with low productivity) play a critical role in explaining the concentration of economic activities...

Toward Economic Diversification in Trinidad and Tobago

Longmore, Rohan; Jaupart, Pascal; Cazorla, Marta Riveira
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
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This paper contributes to the predominant diversification debate that has been ongoing in Trinidad and Tobago for more than three decades. The paper makes a determination of the key impediments to the country's attempts at diversification. Econometric techniques are applied on panel data to identify the most significant obstacles to economic diversification for a set of 183 countries. The results indicate that openness to foreign direct investment inflows is the most fundamental driver of diversification. The findings are then applied to the specific case of Trinidad and Tobago through a detailed analysis of the links in the trends followed by foreign direct investment and diversification between 1980 and 2011. Greater openness to foreign direct investment and improving the business climate appear to be key policies the twin-island republic could implement further in order to expand the range of activities of its economic structure.

Diversificação da agricultura familiar no sul de Minas Gerais: uma análise da percepção de professores e pesquisadores; Diversification of the family agriculture in southern Minas Gerais: an analysis of the university lectures and researchers' perception

Santana, Ana Carolina
Fonte: UNIVERSIDADE FEDERAL DE LAVRAS; DAE - Programa de Pós-graduação; UFLA; BRASIL Publicador: UNIVERSIDADE FEDERAL DE LAVRAS; DAE - Programa de Pós-graduação; UFLA; BRASIL
Tipo: Dissertação
Publicado em 01/08/2014 Português
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The objective of this research was to identify and to describe the perception that researchers and university lectures possess of the diversification as a middle to promote the development of the family farming in the southern Minas Gerais and to confront those professionals' perception with the different social actors' perception identified in the previous studies, family farmers' leaderships, agricultural technicians who advise them and local governments' representatives. With relation to data collection, the technique ‘focused interview’ was used. The interviewee were selected by the non- probabilistic method of sampling by judgment, where six professors and three researchers. The two categories of interviewees this research tend to see the diversification as a favorable development means while its represents for family farmers an income alternative and to reduce economical risks, avoiding in that way, the rural exodus. The main orientation objects that guided the actors' perceptions to consider the diversification as favorable means were the natural resources (climate, soil, hydric resources), infra-structural (structure of road , net of schools, technical attendance and researches related to the agricultural) and location factors...

Trade diversification in Colombia, 1991-2011

Argüello Cuervo, Luis Ricardo
Fonte: Facultad de Economía Publicador: Facultad de Economía
Tipo: info:eu-repo/semantics/book; info:eu-repo/semantics/acceptedVersion Formato: application/pdf
Publicado em //2013 Português
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We describe the evolution of international trade and the behavior of export diversification in Colombia during the period 1991-2011. For measuring trade diversification and following up its behavior along the period, we employ alternative ways of decomposing trade flows along its intensive and extensive margins, using the latter as a measure of diversification. Results indicate that, in the short run, trade diversification in Colombia can be characterized as weak but that there is a modest trend for an increase in its importance. With some differences in degree, for both exports and imports, the number of partner countries increases faster than the number of products contained in the average basket traded and, simultaneously, the number of traded products increases faster than the average number of countries with which they are traded. Hence, trade diversification in Colombia seems to follow a pattern that implies that trade with new partners tends to be relatively slowly populated in terms of products or, from the opposite point of view, trade of new products is relatively sluggish in extending to new partner countries

Differentiated risk models in portfolio optimization: a comparative analysis of the degree of diversification and performance in the São Paulo Stock Exchange (BOVESPA)

Gartner,Ivan Ricardo
Fonte: Sociedade Brasileira de Pesquisa Operacional Publicador: Sociedade Brasileira de Pesquisa Operacional
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2012 Português
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Faced with so many risk modeling alternatives in portfolio optimization, several questions arise regarding their legitimacy, utility and applicability. In particular, a question arises involving the adherence of the alternative models with regard to the basic presupposition of Markowitz's classical model, with regard to the concept of diversification as a means of controlling the relationship between risk and return within a process of optimization. In this context, the aim of this article is to explore the risk-differentiated configurations that entropy can provide, from the point of view of the repercussions that these have on the degree of diversification and on portfolios performance. The reach of this objective requires that a comparative analysis is made between models that include entropy in their formulation and the classic Markowitz model. In order to contribute to this debate, this article proposes that adaptations are made to the models of relative minimum entropy and of maximum entropy, so that these can be applied to investment portfolio optimizations. The comparative analysis was based on performance indicators and on a ratio of the degree of portfolio diversification. The portfolios were formed by considering a sample of fourteen assets that compose the IBOVESPA...

The role of dispersal and adaptive divergence in the diversification and speciation of the tribe Brassiceae and genus Cakile

Willis, Charles George
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2013 Português
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Adaptation is central to our understanding of the origin of biological diversity. Yet whether adaptive divergence promotes the formation of new lineages remains poorly understood. My dissertation addresses the role of adaptive divergence in diversification and speciation. I also investigate an alternative mechanism: dispersal, which can promote diversification and speciation through its effects on gene flow and allopatry. To address the role of divergent adaptation and dispersal in the process of diversification, I take an integrated approach, combining both comparative methods with quantitative genetics to characterize patterns of diversification and speciation in the tribe Brassiceae and genus Cakile. I start with a comparative study of the role of dispersal and adaptation in diversification, and then focus on the role of climatic and latitudinal divergence in the processes of adaptive divergence and speciation. In general, I find limited evidence for the role of divergent adaptation in the evolution of intrinsic reproductive isolation. Diversification in the tribe Brassiceae appears to be mediated by dispersal ability, while in the genus Cakile, the evolution of intrinsic reproductive isolation is largely independent of ecological divergence. Thus...

The Relationship and Causality Testing between Diversification, Risk and Financial Performance: Empirical Examiniation in Taiwan's Banking Industry

Lin, Shu-Ling (Sherry); Wu, Soushan; Penm, Jack HW; Terrell, Richard
Fonte: Inderscience Publishers Publicador: Inderscience Publishers
Tipo: Artigo de Revista Científica
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The objective of this study is to examine the portfolio theory that suggests that diversification can potentially reduce both the return variance and the probability of failure of a portfolio. The study aims to investigate the diversification measure by means of the Hershman-Herfindahl index proposed by Berry [1], and applies the 'diversification index' proposed by Demsetz and Strahan [2,3] by scaling systematic risk with stock return variance of individual banks. It is assumed that as banking has a high diversification index (a high R2), the fraction of risk stemming from firm-specific factors will be small. Next, this study examines the effects of diversification on risk and financial performance, respectively, and finally tests the causality between diversification, risk and financial performance in Taiwan's banking industry for the period 1993-2001. Our paper provides strong evidence of a link between diversification, risk and financial performance of the banking industry in Taiwan. The empirical examinations suggest that diversification may provide an important motive for risk reduction and performance enhancement for the banking industry.