Version of January 2013 Abstract This paper examines the outperformance of naive diversification relative to optimal diversification. From out-of-sample analysis using portfolios consisting of individual stocks as well as diversified equity portfolios, we find that optimal diversification fails to consistently outperform naive diversification. Our results show that naive diversification increas...

Using recent econometric developments about causal inference, I examine whether diversification destroys value. I estimate the value effect of diversification by matching diversifying and single-segment firms on their propensity score-the predicted values from a probit model of the propensity to diversify. I also use Heckman 's (1979) two-stage estimator for comparison purposes. Ifind that on a...

nonfarm activities play an important role in the determination of rural household income, consumption expenditure, and household food security. however, much less studies have been devoted to the factors that influence nonfarm income diversification by farm household in developing countries. using cross-sectional data and a probit model, this study attempts to determine the factors influencing ...

within the broader category of rural tourism, agrotourism is a type of tourism carried out in avery specific environment, mixed livestock and tillage farms. its importance resides in the fact that it offers the possibility of complementing the income generated by the farm with income generated from tourism while at the same time carrying out an activity that promotes the conservation of nature....

china is a vast and overpopulated country in the eastern asia whose energy security and supply is the most important factor of economic growth and consequently, economic, social and political security. by the past decades, its leaders have understood the key role of economic growth and development in the economic and political security of china. thus, they have put all their concentration on th...

changes in credit risk may arise when either the value or the risk of corporate assets changes. changes in the equity value associated with the changes in the asset value and changes in asset risk can be characterized into potentially countervailing direct and indirect effects. the indirect effect of risk on equity value is a function of factors that affect the debt value of including leverage,...

Result diversification is a retrieval strategy for dealing with ambiguous or multi-faceted queries by providing documents that cover as many facets of the query as possible. We propose a result diversification framework based on query-specific clustering and cluster ranking, in which diversification is restricted to documents belonging to clusters that potentially contain a high percentage of r...

Our growing understanding of the plant tree of life provides a novel opportunity to uncover the major drivers of angiosperm diversity. Using a time-calibrated phylogeny, we characterized hot and cold spots of lineage diversification across the angiosperm tree of life by modeling evolutionary diversification using stepwise AIC (MEDUSA). We also tested the whole-genome duplication (WGD) radiation...

Identifying nonrandom clade diversification is a critical first step toward understanding the evolutionary processes underlying any radiation and how best to preserve future phylogenetic diversity. However, differences in diversification rates have not been quantitatively assessed for the majority of groups because of the lack of necessary analytical tools (e.g., complete species-level phylogen...

Informally speaking, diversification of search results refers to a trade-off between relevance and diversity in the set of results. In this article, we present a unifying framework for search result diversification using the axiomatic approach. The characterization provided by the axiomatic framework can help design and compare diversification systems, and we illustrate this using several examp...