Balanced portfolio via signed graphs and spectral clustering in the Brazilian stock market

Quality & Quantity - A portfolio associated with a balanced signed graph that contains both positive and negative edges is more predictable and risk-averse, and is therefore likely to require...     

Mountaineering in Cuba: improvement of true accessibility as an opportunity for regional development of communities outside the tourism enclaves

Mass tourism began in the Caribbean during the middle of the twentieth century. Unfortunately, increasing competition and a change in the motivation of tourists now force the authorities who manage these regions to introduce a new tourism offer that is not based directly on either the 3S (Sun, Sand, and Sea) or 3E (Entertainment, Excitement, Education) model. Hiking, trekking, and climbing, defined as mountaineering, might be one of these. This paper examines the potential for mountaineering in Cuba by verifying its accessibility for tourists. The assessment is based on a framework of true accessibility, which consists of two factors: (1) destination accessibility and (2) real access. Our results show that mountaineering in Cuba should be considered to be one of the key contributors to the development, prosperity, and well-being of all stakeholders, and especially for the communities outside the tourism enclaves.     

How a Reduction of Standard Working Hours Affects Employment Dynamics

December 1, 1996 a new law was implemented in Portugal to gradually reduce the standard workweek from 44 to 40 h. We study how this mandatory reduction affected employment through job creation and job destruction. There was considerable regional, sectoral and firm-size variation in the share of workers who were affected by the working hours reduction. We exploit this variation to assess the impact of the workweek reduction. We find evidence that the working hours reduction had a positive effect on employment through a fall in job destruction.     

Behaviours and entrepreneurial intention: Empirical findings about secondary students

This paper aims to identify some factors that may be explaining differences among secondary students in start-up intentions. For that, the study develops an entrepreneurial intention model sustained by the use of Azjen’s Theory of Planned Behaviour (TBP). Using a sample of students aged between 14 and 15 years old, a questionnaire based on the Li?án and Chen’s Entrepreneurial Intention Questionnaire was administrated. The purpose is to test a model of entrepreneurial intention using structural equations. The findings point that TPB is an appropriate tool to model the development of entrepreneurial intention through pedagogical processes and learning contexts. The education and training should centre itself much more in changing personal attitudes than in knowledge. Moreover, it is desirable that an entrepreneurship educational programme could contribute to the development of competences related to entrepreneurship, social and civic skills, and cultural awareness.     

通过预防召回获得边际竞争优势

对消费品公司来说，产品召回是一个严重的问题。在美国，每年因为安全原因有成千上万的产品被召回。如图1所示，在1999年和2001年间，14个主要类别的消费品的召回数量在稳定地增加。保守地估计，每个公司召回的平均成本多于800万美元，包括对消费者的赔偿。对消费品行业来说，这可以转化为多于60亿美元的成本，这个估计不包括市场信誉造成的销售损失和失去的市场份额。     

Seasonal labor constraints and intra-household dynamics in the female fields of southern Cameroon

African agricultural production is modeled as a sequential decision process, with men's labor first allotted to clearing, then women's labor allotted to harvesting. A switching regression is then used to measure the constraints due to clearing labor capacity and harvesting labor capacity. The import of men's clearing labor depends on the valuation of shadow wages. Output appears to be more frequently constrained by husband's clearing labor, and in this situation male labor appears under‐utilized. However, output is also significantly constrained by female harvest labor, although the findings imply that female labor is over‐utilized at this stage.     

Propensity to firm creation: empirical research using structural equations

The identification of the entrepreneurs’ characteristics and the knowledge of the entrepreneurial profile of university students have been assuming a growing importance in the development of educational programs directed towards the entrepreneurship and start-up processes. This study aims to identify the factors that most contribute for the intention to start up a business. The research also tries to identify the profile of a potential entrepreneur student concerning several characteristics: personal attributes, family, demographic variables and motivations. Research findings include the idea that entrepreneurship education is the most relevant factor in what concerns the propensity to business creation. On the other side, personal characteristics have an important role in shaping motivation to start-up a business and perceived hurdles have a negative impact in the intention to start-up. The results may be relevant when developing an adequate educational program directed to the entrepreneurship education and start-up processes.     

Entrepreneur location decisions across industries

In this paper we analyse whether entrepreneur location decisions differ across industries and identify the factors determining the choice of location between rural and urban environments. Firm location is based on a new taxonomy developed over the influential three dimensions of Hayter’s (1997) approach. The paper uses data from sample of one thousand Portuguese firms. We present a stylized theoretical model to determine how these new five dimensions influence firm’s location and test the model through a logistic regression. Our results show that that the location decisions depend on the sector of activity, type of area (urban vs. rural) and the characteristics of the entrepreneur. We find that companies engaged in knowledge intensive business services prefer to locate in urban areas. From an institutional point of view, firms prefer to locate in rural areas.     

Institutional Environment and Technical Efficiency: A Stochastic Frontier Analysis of Cotton Producers in West Africa

This paper examines the effects of the institutional environment on West African cotton farmers’ technical efficiency (TE). First, key aspects of the cotton sector institutional environment are discussed, including input and credit access, and producers’ organisations. Then, a stochastic frontier production function, which incorporates technical inefficiency effects, is applied to farm level data collected in Benin, Burkina Faso and Mali. The survey includes farmers’ evaluations of the cotton sector institutional environment. Results suggest that institutional level features influence producers’ TE, besides farm‐level characteristics. Cotton growers who report a negative experience with the joint liability programme, who identify the cotton price mechanism or access to credit as the main constraints to performance, and who cultivate more hectares of cereals are technically more inefficient in producing cotton. Findings suggest that cotton farmers in Mali are less technically efficient in producing cotton than in Burkina Faso and Benin. Agricultural development policies focusing on reducing farmers’ financial stress, particularly through the establishment of adequate price mechanisms (i.e. higher farm‐gate prices and timely payments to farmers) and improvement in the input–credit markets should be encouraged to improve TE in West Africa.