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991.
Abstract

This paper presents a simple weighted goal programming model which can be used to predict the current allocation of agricultural enterprises in a particular geographical area. Moreover, it also shows how the approach proposed can be integrated into a multiobjective framework to measure the opportunity cost of maintaining the current situation in terms of several criteria relevant from a private and a public perspective. In this way, the opportunity cost of sustaining the current allocation of agricultural enterprises in the irrigated lands of Tauste (Spain) is assessed in terms of gross margin, employment, seasonal labour and water consumption.  相似文献   
992.
The sub-Saharan Africa challenge programme is designed to address the problems of failures of agricultural markets, inappropriate policies and natural resource degradation, that contribute to the continuing deterioration of livelihoods and food security in the region. It is seeking to do this by redefining the roles of scientists and farmers through collaborative learning processes, addressing questions about the level, timing, type and formof participation, as well as themost effective approaches andmethods to foster them. The research domains of the programme deal with sustainable intensification of smallholder agriculture, the sustainable management of natural resources, the development of efficient markets, and the promotion of enabling policies. One question that was addressed in designing the initiative was deciding where to work so as to maximize the chances of successful testing of this new approach, so that it would lead to significant reductions of rural poverty. A participatory process was put in place to design a framework to accomplish this site selection, and then to apply it in west, east and southern Africa. A mixture of spatial data analysis and expert knowledge on spatial and non-spatial factors was used, and one primary site in each region was identified to form the basis for the next phase of the challenge programme. Several lessons were learnt from the process, including the importance of adapting themethods to actual conditions, the increased utility of targetting when the quantitative and the qualitative are freely combined, and the continued need for baseline spatial and non-spatial data to improve the targeting of research in the future that is designed to alleviate poverty in sub-Saharan Africa.  相似文献   
993.
Road traffic injuries and deaths caused by motor vehicles is a growing public health problem all over the world. Inter-country or regional differences in the pattern of injury by road users have significant implications in determining prevention policies. The present study was conducted to evaluate the pattern of injuries in 217 hospitalized trauma patients admitted during 1 year, 2003. The majority of the injuries (54%) involved motorcycles. The highest incidence amongst the male population was in the age group of 16 - 30 years. Head and face injuries and injuries to the lower limbs comprised 58.1% and 50.7% of all injuries respectively. The bones of the lower limbs were most commonly fractured. To conclude, the traffic casualties of motorcyclists and pedestrians are considered a major problem and the preventive measures to reduce these transport-related injuries are discussed in this study.  相似文献   
994.
Monitoring the mean and the variance of a stationary process   总被引:3,自引:0,他引:3  
We deal with the problem of how deviations in the mean or the variance of a time series can be detected. Several simultaneous control charts are introduced which are based on EWMA (exponentially weighted moving average) statistics for the mean and the empirical variance. The combined X − S2 EWMA chart is extended to time series. Further simultaneous charts are considered. The comparision of these schemes shows that the residual attempt must be favored if a variance change is present.  相似文献   
995.
We provide a preference foundation for decision under risk resulting in a model where probability weighting is linear as long as the corresponding probabilities are not extreme (i.e., 0 or 1). This way, most of the elegance and mathematical tractability of expected utility is maintained and also much of its normative foundation. Yet, the new model can accommodate the extreme sensitivity towards changes from 0 to almost impossible and from almost certain to 1 that has widely been documented in the experimental literature. The model can be viewed as “expected utility with the best and worst in mind” as suggested by Chateauneuf, Eichberger and Grant (Chateauneuf, Alain, Eichberger, Jürgen, Grant, Simon, 2007. Choice under uncertainty with the best and worst in mind: NEO-Additive capacities. Journal of Economic Theory 137, 538–567) or, following our preference foundation, interpreted as “expected utility with consistent optimism and pessimism”.  相似文献   
996.
Although sustainable development is increasingly becoming a part of business plans, it is unclear what makes the economic, social and environmental dynamics strategically compatible. This research examines which of the following in sustainable development – government policy, managerial attitude and stakeholder engagement – is the most influential on the profitability of companies in the UK construction sector. Quantitative and qualitative analyses were rendered through a survey and semi‐structured interviews. Patterns of ambiguity in legislation were discovered as an obstacle for changing the sector's mind‐set. Stakeholder engagement was identified as the defining factor increasing managers' awareness, helping legislation to be effectively implemented and making sustainability highly appealing to clients. These findings indicate that to gain competitive advantage, companies should embark on long‐term strategic alliances which adopt the proposals of environmental non‐governmental organisations and closely follow public opinion. This, strengthens brand equity, allows for premium pricing, increases market share and maximizes profit. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment.  相似文献   
997.
Although service recovery has become an increasingly-studied topic in the operations management literature, robust theories and accompanying empirical studies have only begun to emerge. For example, while many authors have identified and measured the specific activities that are perceived by consumers as effective ways to recover from failure, much less attention has been directed at the systematic structuring of recovery efforts to consistently ensure customer satisfaction and achieve improved, long-term organizational outcomes. Building on recent research that identified the principal constructs of service recovery, this study seeks to explore the relative effectiveness of an integrated service recovery system. Data from 158 service organizations are used to explore the relationship between the system and its associated recovery outcomes. Results indicate that a complete recovery system defined by seven distinct dimensions (formalization, decentralization, comprehensiveness, accessibility, influence, human intensity, and system intensity,) significantly impacts internal capability improvements as well as externally-perceived outcomes (i.e., speed, employee empathy, and recovery effectiveness) while both of these outcomes have a significant impact on customer satisfaction and market performance attributed to service recovery  相似文献   
998.
999.
A quasi-maximum likelihood procedure for estimating the parameters of multi-dimensional diffusions is developed in which the transitional density is a multivariate Gaussian density with first and second moments approximating the true moments of the unknown density. For affine drift and diffusion functions, the moments are exactly those of the true transitional density and for nonlinear drift and diffusion functions the approximation is extremely good and is as effective as alternative methods based on likelihood approximations. The estimation procedure generalises to models with latent factors. A conditioning procedure is developed that allows parameter estimation in the absence of proxies.  相似文献   
1000.
Nationally representative data on family businesses are available in the 1998 Workplace Employee Relations Survey, alongside comparable information for other types of firms. We use these data to compare differences in the use of different consultation and communication procedures. We cover such practices as the use of direct communication schemes (e.g. briefings; the provision of information on financial performance to the workforce) as opposed to indirect methods such as the use of joint consultative committees. There is an a priori expectation in the literature that family-owned businesses are either more likely to use direct forms of communication (vis-à-vis indirect forms) or that they will not be involved in direct communication or consultation with their employees, and we test this using multivariate techniques. Finally, we consider whether the type of consultation/communication structure matters in terms of establishment performance, and what differences exist with respect to family-owned businesses. In particular, this paper tests if those firms that consult directly with staff, as opposed to those that consult through joint consultative committees or trade unions, have higher productivity and/or other measures of performance. Concurrently we test whether there are separate ‘family business’ effects or whether it is generally establishment size that ‘matters’, by estimating a model for family-owned and non-family-owned establishments. In general, our results show that not only do family-owned establishments have lower levels of communication and consultation, but, when the latter is present, this does not generally translate into greater economic benefits (as is the case in non-family-owned firms).  相似文献   
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