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1.
Objective: This study was to determine if calcium fortification yields a higher price per serving in grocery store products. Researchers compared store brand to national brand grocery products in relation to cost in order to examine if calcium values were similar between store brand and national brand products. Methods: A total of 112 store brand and 211 national brand grocery products were collected from three low (national chain store), middle and high priced (Virginia and North Carolina regional store) grocery venues. Products were compared using price and calcium percentage per serving. ANOVA was used to determine between store brand and national brand for price per serving and calcium content, and between grocery venues. Results: National brand fortified products had a significantly lower mean price per serving when compared to national brand non-fortified products (p = 0.0002). There was no statistical difference between store brand fortified and non-fortified products (p = 0.9256). Low priced store brand products had the lowest mean price per serving ($0.34 ±0.24). Conclusions: This study found store brand products have similar calcium content as national brand products. Product cost was lower at low priced store compared to middle and high priced stores.  相似文献   
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Social constructionist theories of gender are utilised to explore the relationship between household accounting and patriarchy during the early twentieth century in the USA and Britain. This period witnessed a reformulation of the ideology of domesticity founded on precepts derived from modish scientific management. It is argued that the suite of calculative techniques prescribed by ‘household engineers’ merely attempted to occupy middle class women in the domestic sphere. Rather than offering a source of professionalisation and liberation, the practice of financial management, costing, record keeping and time and motion study, contributed to a reassertion of private patriarchy, confirmed the gendered nature of spatiality, reinforced the role of woman as a consumer and diverted attention from career building outside the home.  相似文献   
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The Returns to Education: Microeconomics   总被引:8,自引:0,他引:8  
In this paper we focus on education as a private decision to invest in "human capital" and the estimation of the rate of return to that private investment. While the literature is replete with studies that estimate the rate of return using regression methods where the estimated return is obtained as the coefficient on a years of education variable in a log wage equation that contains controls for work experience and other individual characteristics, the issue is surrounded with difficulties. We outline the theoretical arguments underpinning the empirical developments and show that the evidence on private returns to the individual is compelling. Despite some of these issues surrounding the estimation of the return to schooling, our evidence, based on estimates from a variety of datasets and specifications, is that there is an unambiguously positive effect on the earnings of an individual from participation in education. Moreover, the size of the effect seems large relative to the returns on other investments.  相似文献   
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The role of entrepreneurs in stimulating growth in the small business economy has received significant interest in the last three decades. This growing interest is prompted, in part, by the government’s assumption that the establishment and expansion of existing small firms could be greatly enhanced by the promotion of entrepreneurial education programmes in colleges and universities. Whilst there has been significant interest in the role, type and effect of entrepreneurs in the economy, few studies have examined the effect of entrepreneurial programmes on the progression of an idea through to commercialisation. This is because such research, whilst seemingly desirable, is problematic. Evidence can be gleaned through the development of suitable conceptual frameworks and methods, to assess the role and impact of entrepreneurial programmes on the commercialisation of products or processes, and the enhancement of entrepreneurial capabilities. To address this problem, the research will examine different approaches and frameworks that have been developed and applied hitherto. The objective of this will be to highlight the difficulties in assessing the motivations, cognitive and behavioural changes of entrepreneurs. Also, the research will demonstrate the need to undertake adequate controls, which illustrate possible improvement in entrepreneurial capabilities, networks, and credibility in comparison to students that embarked on courses without entrepreneurial elements. The process will confine itself to business development within the higher education (HEI) context. The MSEC has as its remit to provide opportunity, education, awareness and training to foster entrepreneurship within science and engineering departments across four universities in Greater Manchester. This setting will provide a unique situation in which to investigate the development of germinal technology businesses from the inception of an idea to the point of incubation, prototype development and investment. There is a requirement to understand the needs of the virgin entrepreneur, possible obstacles to commercialisation and the process of new venture creation. The methodology to be adopted has been identified, and forges new ground on combining positivist and phenomenological paradigms. The multi–paradigm approach supports the use of critical incident technique to reveal greater insights in to the personal and cognitive development of virginal entrepreneurs, the suitability of enterprise programmes to act as catalysts for venture creation, and their role in supporting technology transfer. The research will not only confine itself to examining undergraduate and postgraduate projects within MSEC’s business creation unit, but will also continue to assess the experience of entrepreneurs’ when they leave the programme. The research also documents the economic contribution of the programme, in terms of generation of new technology–based firms and the impact of entrepreneurs joining established small firms. Ultimately the aim is to build a long–term picture of the role of enterprise programmes in HEIs that will inform policy and practice.  相似文献   
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Stochastic dominance efficiency criteria are used to rank the net farm return distributions for four different tillage systems under six different farm scenarios. Pairwise comparisons of tillage systems are carried over incremental upper and lower risk-aversion coefficient (RAC) bounds identified for each farm scenario, based on the size and spread of the outcome distributions to identify regions where dominance may switch between tillage systems. Ridge-till systems are generally the dominant tillage system for all farm scenarios considered. No-till systems on clay loam soils are more dominant in the risk-preferring range and less dominant in the risk-averse range, which relates to the relatively larger range of net return values and smaller mean net return values generated by this tillage system. Conversely, the moldboard plow and chisel plow systems are more dominant in risk-aversion intervals and less dominant in the risk-preferring intervals for clay loam soils. In sandy soil scenarios, the ridge-till and no-till systems are dominant over the two fall tillage systems for all farm sizes, indicating that these tillage systems are more competitive with conventional tillage systems in lighter soil type situations. A sensitivity analysis between moldboard plow and no-till systems indicates that no-till would dominate in risk-preferring intervals, and an increase in no-till net farm returns of 16 per acre would change dominance in favor of no-till in risk-averse interval space. On a utilisé les critères d'efficacitéà dominance stochastique pour classer les divers niveaux de recettes agricoles nettes dans quatre systèmes différents de travail du sol, selon six scénarios d'exploitation. Des comparaisons en paires des systèmes de travail ont été faites en regard de tranches croissantes des limites supérieures et inférieures du coefficient d'aversion du risque (CER), établies pour chaque scénario d'après l'importance et l'étendue des distributions du rendement, dans le but d'identifier les régions où la dominance serait susceptible de passer d'un système de travail à l'autre. Le système de travail sur billons était en général le système dominant dans tous les scénarios d'exploitation examinés. La culture sans travail du sol sur loam argileux était plus dominante dans les intervalles d'acceptation du resque et moins dominante dans les intervalles d'aversion du resque, cequi s'explique au fait que ce système de travail donne lieu à une fourchette relativement plus large, mais aussi à une moyenne plus faible du revenu net. À l'inverse, le labour à la charrue classique et au chisel dominait davantage dans les intervalles d'aversion du risque. Dans les sols sableux, le travail sur billons et la culture sans labour l'emportaient sur les deux autres régimes dans toutes les tailles d'exploitation, ce qui porte à croire que, dans les sols plus légers, ces régimes sont plus concurrentiels avec les systèmes classiques. L'analyse de sensibilité entre le labour à la charrue et les systèmes sans travail du sol montre que ces derniers dominent dans les intervalles d'acceptation du risque et qu'un accroissement du revenu agricole net de 16 /acre ferait glisser la dominance vers les intervalles d'aversion du risque.  相似文献   
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Statistical Decision Problems and Bayesian Nonparametric Methods   总被引:1,自引:0,他引:1  
This paper considers parametric statistical decision problems conducted within a Bayesian nonparametric context. Our work was motivated by the realisation that typical parametric model selection procedures are essentially incoherent. We argue that one solution to this problem is to use a flexible enough model in the first place, a model that will not be checked no matter what data arrive. Ideally, one would use a nonparametric model to describe all the uncertainty about the density function generating the data. However, parametric models are the preferred choice for many statisticians, despite the incoherence involved in model checking, incoherence that is quite often ignored for pragmatic reasons. In this paper we show how coherent parametric inference can be carried out via decision theory and Bayesian nonparametrics. None of the ingredients discussed here are new, but our main point only becomes evident when one sees all priors—even parametric ones—as measures on sets of densities as opposed to measures on finite-dimensional parameter spaces.  相似文献   
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Previous research in the areas of tournaments, human capital, and learning theory have shown that promotion is a function of human capital, experience, ability, and wage growth. These variables were used to estimate a Cox regression using data from a single firm. The survival rates for a Cox regression and an up-or-out regression model are computed. The results suggest that certain up-or-out models are valid even when the firm does not have such a policy and show that an up-or-out procedure predicts the promotion and exit survival rates as well as a Cox regression.  相似文献   
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