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11.
While body fat is the most accurate measure of obesity, its measurement requires special equipment that can be costly and time consuming to operate. Attention has thus typically focused on the easier to calculate body mass index (BMI). However, the ability of BMI to accurately identify obesity has been increasingly questioned. This paper focuses attention on whether more general body mass indices are appropriate measures of body fat. Using a data set of body fat, height, and weight measurements, general models are estimated which nest a wide variety of weight–height indices as special cases. In the absence of a race and gender categorisation, the conventional BMI was found to be the appropriate index with which to predict body fat. When such a categorisation was made, however, the BMI was never selected as the appropriate index. In general, predicted female body fat was some 10 kg higher than that of a male of identical build and predicted % body fat was over 11 percentage points higher, but age effects were smaller for females. Considerable racial differences in predicted body fat were found for males, but such differences were less marked for females. The implications of this finding for interpreting recent research on the effect of obesity on health, society, and economic factors are considered.  相似文献   
12.
Concept mapping is now a commonly-used technique for articulating and evaluating programmatic outcomes. However, research regarding validity of knowledge and outcomes produced with concept mapping is sparse. The current study describes quantitative validity analyses using a concept mapping dataset. We sought to increase the validity of concept mapping evaluation results by running multiple cluster analysis methods and then using several metrics to choose from among solutions. We present four different clustering methods based on analyses using the R statistical software package: partitioning around medoids (PAM), fuzzy analysis (FANNY), agglomerative nesting (AGNES) and divisive analysis (DIANA). We then used the Dunn and Davies-Bouldin indices to assist in choosing a valid cluster solution for a concept mapping outcomes evaluation. We conclude that the validity of the outcomes map is high, based on the analyses described. Finally, we discuss areas for further concept mapping methods research.  相似文献   
13.
The socio-economic literature has focused much on how overall inequality in income distribution (frequently measured by the Gini coefficient) undermines the “trickle down” effect. In other words, the higher the inequality in the income distribution, the lower is the growth elasticity of poverty. However, with the publication of Piketty’s magnum opus (2014), and a subsequent study by Chancel and Piketty (2017) of evolution of income inequality in India since 1922, the focus has shifted to the income disparity between the richest 1% (or 0.01%) and the bottom 50%. Their central argument is that the rapid growth of income at the top end of millionaires and billionaires is a by-product of growth. The present study extends this argument by linking it to poverty indices in India. Based on the India Human Development Survey 2005–12 – a nationwide panel survey-we examine the links between poverty and income inequality, especially in the upper tail relative to the bottom 50%, state affluence (measured in per capita income) and their interaction or their joint effect. Another feature of our research is that we analyse their effects on the FGT class of poverty indices. The results are similar in as much as direction of association is concerned but the elasticities vary with the poverty index. The growth elasticities are negative and significant for all poverty indices. In all three cases, the disparity between the income share of the top 1% and share of the bottom 50% is associated with greater poverty. These elasticities are much higher than the (absolute) income elasticities except in the case of the poverty gap. The largest increase occurs in the poverty gap squared – a 1% greater income disparity is associated with a 1.24% higher value of this index. Thus the consequences of even a small increase in the income disparity are alarming for the poorest.  相似文献   
14.
The 2008 spike in world grain prices is widely recognised to have had serious impacts on food security and poverty, but these high grain prices are commonly described as low in historical terms – an inconsistency resulting from the use of advanced‐ and global‐economy price indices in calculating real prices. This ignores the high share of food in poor people's expenditures and the indirect effects of income growth on expenditure patterns of rich consumers. Poor consumers have not experienced the same falls in real food prices and are more vulnerable to price shocks. Different price indices must be developed to take account of differences between consumer groups.  相似文献   
15.
An assessment is made of the number of observations on ordinal data necessary for reasonable power in a significance test of the null hypothesis of a logit model versus an alternative of a complementary log-log and vice versa. The conclusion is that quite modest numbers of observations, e.g. 50-100, are adequate provided that the boundaries of the ordinal scale are suitably defined.  相似文献   
16.
Symmetrical global sensitivity analysis (SGSA) can help practitioners focusing on the symmetrical terms of inputs whose uncertainties have an impact on the model output, which allows reducing the complexity of the model. However, there remains the challenging problem of finding an efficient method to get symmetrical global sensitivity indices (SGSI) when the functional form of the symmetrical terms is unknown, including numerical and non-parametric situations. In this study, we propose a novel sampling plan, called symmetrical design, for SGSA. As a preliminary experiment for model feature extracting, such plan offers the virtue of run-size economy due to its closure respective to the given group. Using the design, we give estimation methods of SGSI as well as their asymptotic properties respectively for numerical model and non-parametrical model directly by the model outputs, and further propose a significance test for SGSI in non-parametric situation. A case study for a benchmark of GSA and a real data analysis show the effectiveness of the proposed design.  相似文献   
17.
企业技术竞争力评价指标体系研究:构建、测评与结论   总被引:3,自引:1,他引:3  
在分析企业技术竞争力内涵的基础上构建了企业技术竞争力评价指标体系,尝试利用层次分析法对该指标体系进行测评,通过构造判断矩阵并伴随一致性检验,得到了各指标体系的总排序结果。研究表明,从准则层的3项目标来看,企业的技术创新竞争力对总目标的影响权重占有绝对优势;从指标层的29项评价指标来看,影响最大的10项指标在对总目标的影响权重值中占大部分比例,这些指标是提升企业技术竞争力水平的关键所在。  相似文献   
18.
论现金制的财务预警分析   总被引:3,自引:0,他引:3  
企业财务预警分析的关键在于预警指数的测度.从企业危机的预警机理出发,选取能反映企业安全性的"现金制"指标.指标临界值考虑了企业规模和所处的行业,从企业的经营、投资和筹资等三方面设置了个体财务预警指数.并由此得出了综合财务预警指数,实例检验结果表明该预警指数是有效的.  相似文献   
19.
本文通过对十二个大麦品种籽粒灌浆“S”曲线的描绘,发现决定粒重的关键时期是在开花后22~37天,此期积累的物质占最大粒重的60%以上,单粒体积一般在开花后37天前后达到最大值。籽粒含水量在开花台47天就迅速降到20%左右。  相似文献   
20.
A robust process minimises the effect of the noise factors on the performance of a product or process. The variation of the performance of a robust process can be measured through modelling and analysis of process robustness. In this paper, a comprehensive methodology for modelling and analysis of process robustness is developed considering a number of relevant tools and techniques such as multivariate regression, control charting and simulation within the broad framework of Taguchi method. The methodology as developed considers, in specific terms, process modelling using historical data pertaining to responses, inputs variables and parameters as well as simulated noise variables data, identification of the model responses at each experimental setting of the controllable variables, estimation of multivariate process capability indices and control of their variability using control charting for determining optimal settings of the process variables using design of experiment-based Taguchi Method. The methodology is applied to a centrifugal casting process that produces worm-wheels for steam power plants in view of its critical importance of maintaining consistent performance in various under controllable situations (input conditions). The results show that the process settings as determined ensure minimum in-control variability with maximum performance of the centrifugal casting process, indicating improved level of robustness.  相似文献   
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