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171.
Statistical Thinking in Empirical Enquiry   总被引:4,自引:0,他引:4  
This paper discusses the thought processes involved in statistical problem solving in the broad sense from problem formulation to conclusions. It draws on the literature and in-depth interviews with statistics students and practising statisticians aimed at uncovering their statistical reasoning processes. From these interviews, a four-dimensional framework has been identified for statistical thinking in empirical enquiry. It includes an investigative cycle, an interrogative cycle, types of thinking and dispositions. We have begun to characterise these processes through models that can be used as a basis for thinking tools or frameworks for the enhancement of problem-solving. Tools of this form would complement the mathematical models used in analysis and address areas of the process of statistical investigation that the mathematical models do not, particularly areas requiring the synthesis of problem-contextual and statistical understanding. The central element of published definitions of statistical thinking is "variation". We further discuss the role of variation in the statistical conception of real-world problems, including the search for causes.  相似文献   
172.
The long-term structure of production, factor demand and factor productivity in the Canadian pulp and paper industry was studied for the period 1956 to 1982. A four input (labor, capital, material and energy) nonhomothetic translog cost function was used for the purpose. Least-cost combinations of the four factors were obtained by imbedding an interrelated dynamic adjustment process. These least-cost paths, from which the cyclical fluctuations due to business turns were filtered out, were then used to derive the long-term productivity of each input. Long-term elasticities of substitution and demand were also computed. Long-term and short-term results were compared. Important findings of the study were: (i) the long-term structure of production of the industry can be represented by the nomothetic version of the translog cost function, (ii) the long-term technological progress in the industry is slow despite evidence of some economies of scale in production, (iii) all factors of production in the industry are long-run substitutes despite short-run complementarities between some factors of production, (iv) each input was observed to be misallocated during the period of study as compared to the least-cost allocations, (v) observed productivity growth of capital, labor and energy declined during the seventies and early eighties, as compared to growth in the sixties, but growth in their long-run productivities did not, (vi) though both observed and long-run productivities of raw material declined the rate of decline was lower on the long-run path, and (vii) price increases in the pulp and paper industry after 1971 could have been lower than what was actually experienced if the industry could change with economic circumstances more rapidly. La structure à long terme de production, de facteur de demande et de facteur de productivité dans l'industrie canadienne de putpe et de papier est étudiée pour la période de 1956 à 1982. Une fonction de coût “nonhomothetic translog” avec quatre entrées (la main-d'oeuvre, le capital, le matériel et l‘énergie) est utilisée pour cette étude. Les combinaisons les moins chères des quatre facteurs sont obtenues en incluant un ajustement dynamique du processus d'interaction. Ces chemins les moins chers, desquels les fluctuations conjoncturelles dues aux changements d'affaires sont enlevées, sont utilisés pour dériver la productivité à long terme de chaque entrée. Les élasticités à long terme de substitution et de demande sont aussi calculées. Les résultats à long terme et ceux à court terme sont comparés. Les découvertes importantes de cette étude sont: (i) la structure à long terme de production de l’-industrie peut être représentée par la version “homothetic” de la fonction de coût “translog,” (ii) le progrès technologique à long terme dans l'industrie est lent malgré l‘évidence de certaines économies par la production à grande échelle, (iii) tous les facteurs de production dans l'industrie sont des substituts à long terme malgré les complémentarités à court terme parmi les facteurs de production, (iv) chaque entrée était allouée au mauvais endroit pendant la période d’étude à comparaison des allocations les moins chères, (v) la croissance de productivité observée de capital, de main-d'oeuvre et d‘énergie a diminué pendant les années soixante-dix et au début des années quatre-vingts, à comparaison de la croissance dans les années soixante, mais la croissance de leurs productivités à long terme n'a pas diminué, (vi) bien que les productivités observées et à long terme de matières premières ont diminué, les taux de diminution sont plus bas sur le chemin à long terme, et (vii) les augmentations de prix dans l'industrie de pulpe et de papier après 1971 auraient pu être plus bas qu'on n'a expérimenté si l'industrie était capable de changer plus rapidement selon les circonstances économiques.  相似文献   
173.
The Core-Walras Equivalence is examined in a finite or infinite economy in which the competitive gap is bounded by the size of the atoms in the economy. The economy is represented by a Boolean algebra of coalitions, and coalitions rather than individual agents are taken as a primitive concept. Coalition arbitrage plays the central role in our analysis.  相似文献   
174.
In order for farmers to accept improved soil and water management practices, new technologies must be appropriate to the specific site conditions found in the farm setting and be consistent with farmers' objectives and available resources. A whole-farm modeling analysis of this problem is described. Preliminary estimates of the benefits of increased soil moisture conservation for representative low-resource farmers in Mali are presented. If farmers could improve rainfall infiltration from currently low rates of about 40% up to 60%, and use small amounts of chemical fertilizers, disposable income could increase two to four times depending on rainfall. Income could be increased another 50% if the infiltration rate was raised to 80%. Food grain production could increase 60 to 90% with improved moisture conservation and fertilizer use.  相似文献   
175.
Fear has been widely expressed that the modern rice varieties have created large disparities in regional income distribution, as the productivity gap between favorable and unfavorable rice-production environments widened due to differential technology adoption throughout South and Southeast Asia over the last two decades. Technology affects the income of farm population directly through its effects on productivity and factor use, and indirectly through its effect on factor prices. In particular, the ultimate distributional impact of modern varieties will critically depend on the interregional labor-market adjustments through migration in response to regional wage differentials created by the differential technology adoption, since labor is the main resource of the majority of the rural population. We studied favorable and unfavorable rice-growing villages in the Philippines, and found that adoption of modern varieties during the 1970s was positively related to population growth rate. Contrary to popular belief, no association was observed between wage rates and adoption of modern varieties as of 1986. These findings support the hypothesis that the differential adoption of modern rice varieties induced interregional labor migration toward equalization of wage income across different production environments.  相似文献   
176.
177.
Global leaders agree on the need to substantially decarbonize the global economy by 2050. This paper compares potential costs associated with different policy pathways to achieve tourism sector emission reduction ambitions (?50% by 2035) and transform the sector to be part of the mid-century decarbonized economy (?70% by 2050). Investment in emissions abatement within the tourism sector, combined with strategic external carbon offsets, was found to be approximately 5% more cost effective over the period 2015–2050 than exclusive reliance on offsetting. The cost to achieve the ?50% target through abatement and strategic offsetting, while significant, represents less than 0.1% of the estimated global tourism economy in 2020 and 3.6% in 2050. Distributed equally among all tourists (international and domestic), the cost of a low-carbon tourism sector is estimated at US$11 per trip, equivalent to many current travel fees or taxes. Exclusive reliance on offsetting would expose the sector to extensive and continued carbon liability costs beyond mid-century and could be perceived as climate inaction, increasing reputational risks and the potential for less efficient regulatory interventions that could hinder sustainable tourism development. Effective tourism sector leadership is needed to develop a strategic tourism policy framework and emission measurement and reporting system.  相似文献   
178.
The tourism industry can negatively affect wildlife, plants and natural ecosystems through habitat destruction, pollution, over-exploitation of natural resources and visitor impacts to sensitive ecosystems. One approach to mitigate such threats is the application of voluntary sustainability standards, supported by training of tourism enterprises and verified by external audits. The Rainforest Alliance standard defines 78 criteria (requirements) for sustainable environmental, social and business practices, and has been adopted by over 600 tourism enterprises – including hotels, lodges and tour boats – in 12 countries. We examined the performance of 106 hotels in six Latin American countries against 29 of the sustainable tourism criteria most directly related to biodiversity conservation. Independent audits were used to assess hotel performance at baseline followed by a repeat assessment after training, about two years later. Mean conformance with the 29 biodiversity criteria increased significantly during this interval, from 44% to 58%. Improvements were greatest for businesses in the lowest third of performance at baseline (laggards) and smallest for hotels in the highest third (leaders). The results indicate that a voluntary sustainability standard and training program can serve both to recognize existing good actors and to drive incremental improvement in enterprises that were previously less sustainable.  相似文献   
179.
Self-efficacy influences students’ activities, effort and persistence, and it can help predict their motivation and academic performance. This study attempts to investigate the relationship between self-efficacy, preferred learning methods, and academic performance under different learning methods in a unique hospitality course setting. The results indicate that hospitality management students prefer a “learn by doing” approach instead of computer-based learning and lecturing. This study concludes that self-efficacy affects the academic performance in both lecturing and practical learning in hospitality education. However, students’ preference in terms of learning methods does not influence their academic performance. Emphasizing “learn by doing” in the hospitality higher education curriculum is recommended in addition to recruiting faculty members with extensive industry experience. Conversely, it is recommended that faculty find the means to increase students’ self-efficacy when adopting different teaching approaches.  相似文献   
180.
To achieve sustainability in heritage tourism, tourists should be placed at the heart of the management and planning processes. Indicators and standards-based frameworks were developed in the field of outdoor recreation management to manage and measure crowding and other problematic issues in parks and related areas. Using normative theory and visual research methods, this article aims to examine crowding standards of tourists at Petra Archaeological Park, and compare these standards between the types of heritage tourists suggested by a model developed by Bob McKercher. Results showed that tourists’ acceptability levels go down with an increasing number of tourists, and tourists who are highly motivated to visit heritage sites (i.e. purposeful and sightseeing heritage tourists) had the most restrictive acceptable number of tourists at the park. The normative standards formulated in this article provided a guidance to manage crowding at Petra.  相似文献   
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