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331.
There is growing concern regarding cost and time overruns in public projects. However, despite the extensive literature on the subject, there is relatively little research on the impact of time overruns on cost overruns. This study assesses whether larger time deviations can lead to larger cost deviations. Our hypothesis is that a project with a time overrun is more likely to also have a cost overrun. The authors used a sample of 208 projects in Portugal, with data collected from the Portuguese Court of Auditors. Using the data, a number of econometric models were developed: Ordinary Least Squares, Generalized Linear Model, Tobit, and Probit. The instrumented variables and structural equation modelling techniques were applied to address potential endogeneity in the data. The analysis was controlled for factors such as political, governance, economic, and project variables. The results suggest that larger time deviations are associated with larger cost deviations. The inference is that projects that take longer to complete also tend to suffer from cost overruns.  相似文献   
332.
Worldwide, obesity almost tripled between 1975 and 2016 and is now prevalent in both rich and poor countries. Using annual food availability data produced by the Food and Agriculture Organisation of the United Nations (FAO) covering half a century in 118 countries, this article explores the diets that are central to the problem of obesity, identifying groups of countries with similar consumption patterns. Applying algorithms from the fuzzy clustering literature, five distinct consumption patterns are revealed whose dietary composition broadly corresponds to diets that we label ‘Western’, ‘Traditional’, ‘Mediterranean’, ‘Tropical’ and ‘Vegetarian’. Despite differences in dietary characteristics, all five share two common themes: rising total calories and declining healthiness, both of which are linked to the substitution of plant-based foods with food derived from animals. That the evidence points to a convergence on the ‘Western’ diet, the most obesogenic and least healthy of all the diets we consider, is a cause for concern. The key message is that in a future where people are predicted to live longer – but not necessarily healthier – lives, recent efforts to address the challenge are prescient, and as the results in the article imply, need to be heeded globally.  相似文献   
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