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371.
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This paper contributes to the literature on the effect of venture capital (VC) on the economic development of areas in which those specialized investors are active. The work focuses on the separate consideration of two effects that are supposed to explain the superior performance of a large sample of Spanish VC-backed firms, namely funding and value-added services provided by VC managers to their investee firms. The results show that funding is significant regardless of the stage of development of the investee firm. The value added, however, is only significant for the subsample of firms at the expansion stage.  相似文献   
373.
The oil supply chain is facing new challenges due to emerging issues such as new alternative energy sources, oil sources scarcity, and price variability with high impact on demand and production and profit margins reduction. Additionally, the existence of large, complex and world wide spread businesses implies a complex system to be managed where distribution can be seen as one of the key areas that needs to be efficiently and effectively managed. Different types of distribution modes characterize the oil supply chain where the pipeline mode is one of the most complex to operate when having multiproduct characteristics. This paper addresses the planning of a generic oil derivatives transportation system characterized by a multiproduct pipeline that connects a single refinery to a storage tank farm. Two alternative mixed integer linear programming models (MILP) that aim to attain a set of planning objectives such as fulfilling costumers’ demands (which is mandatory) while minimizing the medium flow rate are developed. Additionally, final inventory levels are avoided to be excessively low. A real world scenario of a Portuguese company is used to validate and compare the two alternative MILP models developed in this paper.  相似文献   
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375.
AStA Advances in Statistical Analysis - We herein introduce variable selection procedures based on depth similarity, aimed at identifying a small subset of variables that can better explain the...  相似文献   
376.
This study analysed, from a social justice perspective, how students from two Chilean public schools evaluate, legitimise and delegitimise processes and social actors associated with classroom well-being. Using a participatory qualitative design, fifty-nine (59) seventh grade students were asked to take and then select photographs about their school experience, and later participated in semi-structured interviews and a group workshop. Findings regarding the classroom context showed that children legitimised active learning methodologies, teachers to whom they feel close, and the use of technology for learning. They delegitimised punishment and teachers who ignored minority students or those with learning difficulties.  相似文献   
377.
We introduce a new centrist or intermediate inequality concept, between the usual relative and absolute notions, which is shown to be a variant of the α-ray invariant inequality measures in Pfingsten and Seidl (1997). We say that distributions x and y have the same (x, π)-inequality if the total income difference between them is allocated among the individuals as follows: 100π% preserving income shares in x, and 100(1−π)% in equal absolute amounts. This notion can be made as operational as current standard methods in Shorrocks (1983). Received: 13 May 1998/Accepted: 25 January 1999  相似文献   
378.
We present here a direct elementary construction of continuous utility functions on perfectly separable totally preordered sets that does not make use of the well-known Debreu’s open gap lemma. This new construction leans on the concept of a separating countable decreasing scale. Starting from a perfectly separable totally ordered structure, we give an explicit construction of a separating countable decreasing scale, from which we show how to get a continuous utility map.   相似文献   
379.
Innovation is nowadays a fundamental determinant of value creation in business companies and economic growth. Therefore, the measurement of innovation has become a significant concern both for business companies and governments. Traditionally, attempts to measure innovation have adopted a macroeconomic approach, as they have been largely based on broad surveys. However, no attempt has been made to date in order to complement the information provided by such surveys with aggregated data obtained from the financial reports of individual companies. This paper analyses the conceptual and methodological problems underlying the measurement of business innovation by means of surveys and discusses the lack of ability of accounting standards to accurately reflect innovative activities in the financial statements of business firms.In the light of the evidence provided by the empirical studies published to date, we analyse the Spanish situation by reviewing innovation studies conducted by the National Institute of Statistics (INE), and assessing the relationship between the value relevance of accounting information and the firm's technological level. Our results suggest that both, micro- and macroeconomic approaches towards the measurement of innovation have significant shortcomings. Thus, a joint effort seems to be needed in order to overcome the methodological limitations affecting innovation studies based on surveys and those relying on financial accounting information. Despite their limitations, surveys provide a sound basis for the identification of trends, key factors and explanatory variables. On the other hand, financial statements could provide a sound basis for the measurement of innovation if they included more relevant information on the intangible determinants of the value of companies. This has obvious implications for the standard setting process.  相似文献   
380.
This paper reviews changes in homogamy by migration status and educational level in Monterrey, Mexico, through the analysis of marriage patterns for two cohorts of men born in 1905–1934 and 1940–1969. Results show a significant increase in educational homogamy, as well as in homogamy by rural origins. The changes suggest that education has played an increasingly important role in the process of mate selection, although certain particularistic characteristics, such as being a rural immigrant, are still important in marriage formation. The paper concludes with a discussion of the implications of these findings for the relationship between homogamy and social stratification.
Patricio SolísEmail:
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