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211.
Perry C. Oddo Ben S. Lee Gregory G. Garner Vivek Srikrishnan Patrick M. Reed Chris E. Forest Klaus Keller 《Risk analysis》2020,40(1):153-168
Sea levels are rising in many areas around the world, posing risks to coastal communities and infrastructures. Strategies for managing these flood risks present decision challenges that require a combination of geophysical, economic, and infrastructure models. Previous studies have broken important new ground on the considerable tensions between the costs of upgrading infrastructure and the damages that could result from extreme flood events. However, many risk-based adaptation strategies remain silent on certain potentially important uncertainties, as well as the tradeoffs between competing objectives. Here, we implement and improve on a classic decision-analytical model (Van Dantzig 1956) to: (i) capture tradeoffs across conflicting stakeholder objectives, (ii) demonstrate the consequences of structural uncertainties in the sea-level rise and storm surge models, and (iii) identify the parametric uncertainties that most strongly influence each objective using global sensitivity analysis. We find that the flood adaptation model produces potentially myopic solutions when formulated using traditional mean-centric decision theory. Moving from a single-objective problem formulation to one with multiobjective tradeoffs dramatically expands the decision space, and highlights the need for compromise solutions to address stakeholder preferences. We find deep structural uncertainties that have large effects on the model outcome, with the storm surge parameters accounting for the greatest impacts. Global sensitivity analysis effectively identifies important parameter interactions that local methods overlook, and that could have critical implications for flood adaptation strategies. 相似文献
212.
Roderick G. Galam 《Journal of youth studies》2018,21(8):1045-1060
This article examines how young Filipino men looking to work in international seafaring deploy servitude as a means of attaining education-to-work transition. It focuses on those applying to work for free as ‘utility men’ (gofer or flunkey) in Manila’s manning and crewing agencies that supply seafarers to ship operators around the world in exchange for the promise of boarding a ship. Based on participant observation and life history interviews, the article accounts for how they transform their servitude into diskarte – strategy by which they navigate the limited employment opportunities in the Philippines – by constructing their ‘utility manning’ as an informal and negotiated pathway to employment. The young Filipino men’s seeking and enduring servitude, geared towards gleaning better social possibilities, becomes a profoundly rational act of investing in and securing their future. 相似文献
213.
Demographic ageing is a challenge for many countries. Even though Turkey has a relatively younger demographic composition, the proportion of the older people (65+) within the population is rapidly increasing. Within this framework, older people are becoming more important clients for both social work students and social workers in Turkey. This study aims to reveal the attitudes of social work students towards older people and determine the various factors that affect their views on older persons. In the scope of the project, Kogan's Attitude Towards Old People Scale was applied to 419 social work undergraduate students at a university located in Central Anatolia. The findings showed that social work students scored a mean of 130.96 and they generally had positive attitudes towards older people. The correlation between year of study, gender and age was not statistically significant. However, having lived mostly in urban areas was positively correlated with the mean Kogan scores and this finding was found to be statistically significant. Exposure to personal contact with older people at both the personal and professional levels was influential in shaping attitudes about the older people. 相似文献
214.
215.
The disease burden of pathogens as estimated by QMRA (quantitative microbial risk assessment) and EA (epidemiological analysis) often differs considerably. This is an unsatisfactory situation for policymakers and scientists. We explored methods to obtain a unified estimate using campylobacteriosis in the Netherlands as an example, where previous work resulted in estimates of 4.9 million (QMRA) and 90,600 (EA) cases per year. Using the maximum likelihood approach and considering EA the gold standard, the QMRA model could produce the original EA estimate by adjusting mainly the dose‐infection relationship. Considering QMRA the gold standard, the EA model could produce the original QMRA estimate by adjusting mainly the probability that a gastroenteritis case is caused by Campylobacter. A joint analysis of QMRA and EA data and models assuming identical outcomes, using a frequentist or Bayesian approach (using vague priors), resulted in estimates of 102,000 or 123,000 campylobacteriosis cases per year, respectively. These were close to the original EA estimate, and this will be related to the dissimilarity in data availability. The Bayesian approach further showed that attenuating the condition of equal outcomes immediately resulted in very different estimates of the number of campylobacteriosis cases per year and that using more informative priors had little effect on the results. In conclusion, EA was dominant in estimating the burden of campylobacteriosis in the Netherlands. However, it must be noted that only statistical uncertainties were taken into account here. Taking all, usually difficult to quantify, uncertainties into account might lead to a different conclusion. 相似文献
216.
Gauss M. Cordeiro Morad Alizadeh Thiago G. Ramires Edwin M. M. Ortega 《统计学通讯:理论与方法》2017,46(11):5685-5705
We introduce and study general mathematical properties of a new generator of continuous distributions with one extra parameter called the generalized odd half-Cauchy family. We present some special models and investigate the asymptotics and shapes. The new density function can be expressed as a linear mixture of exponentiated densities based on the same baseline distribution. We derive a power series for the quantile function. We discuss the estimation of the model parameters by maximum likelihood and prove empirically the flexibility of the new family by means of two real data sets. 相似文献
217.
In the 1970s motion picture studios increased their use of blind bidding and nonrefundable guarantees in an attempt to reduce the risks associated with producing a small number of large budget films. However, theater owners claimed that blind bidding and guarantees shifted risk to them and increased the likelihood of bankruptcy, because they were required to bid for the right to exhibit a movie without seeing it first. In response to the lobbying of theater owners, 24 states passed laws between 1978 and 1984 that banned blind bidding, while 7 states also banned nonrefundable guarantees. This paper provides the first empirical analysis of the conflicting claims made by theater owners and movie studios about the impact of these laws on the survival rates of independent theaters, admission prices, and delays in the release of movies. We find that the laws were not only ineffective in keeping theater owners at risk of bankruptcy from exiting the market; they may have been even detrimental to those theater owners converting theaters to multiplexes at that time. (JEL K, L) 相似文献
218.
Astrid M. G. Poorthuis Sander Thomaes Marcel A. G. van Aken Jaap J. A. Denissen Bram Orobio de Castro 《Social Development》2014,23(4):770-783
The transition from primary to secondary school challenges children's psychological well‐being. A cross‐transitional longitudinal study (N = 306; mean age = 12.2 years) examined why some children's self‐esteem decreases across the transition whereas other children's self‐esteem does not. Children's expected social acceptance in secondary school was measured before the transition; their actually perceived social acceptance was measured after the transition. Self‐esteem and Big Five personality traits were measured both pre‐ and posttransition. Self‐esteem changed as a function of the discrepancy between children's expected and actually perceived social acceptance. Furthermore, neuroticism magnified self‐esteem decreases when children's ‘hopes were dashed'—when they experienced disappointing levels of social acceptance. These findings provide longitudinal support for sociometer theory across the critical transition to secondary school. 相似文献
219.
Stéphane Helleringer Gilles Pison Almamy M. Kanté Géraldine Duthé Armelle Andro 《Demography》2014,51(2):387-411
Estimates of adult mortality in countries with limited vital registration (e.g., sub-Saharan Africa) are often derived from information about the survival of a respondent’s siblings. We evaluated the completeness and accuracy of such data through a record linkage study conducted in Bandafassi, located in southeastern Senegal. We linked at the individual level retrospective siblings’ survival histories (SSH) reported by female respondents (n = 268) to prospective mortality data and genealogies collected through a health and demographic surveillance system (HDSS). Respondents often reported inaccurate lists of siblings. Additions to these lists were uncommon, but omissions were frequent: respondents omitted 3.8 % of their live sisters, 9.1 % of their deceased sisters, and 16.6 % of their sisters who had migrated out of the DSS area. Respondents underestimated the age at death of the siblings they reported during the interview, particularly among siblings who had died at older ages (≥45 years). Restricting SSH data to person-years and events having occurred during a recent reference period reduced list errors but not age and date errors. Overall, SSH data led to a 20 % underestimate of 45 q 15 relative to HDSS data. Our study suggests new quality improvement strategies for SSH data and demonstrates the potential use of HDSS data for the validation of “unconventional” demographic techniques. 相似文献
220.