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231.
Campylobacter QMRA: A Bayesian Estimation of Prevalence and Concentration in Retail Foods Under Clustering and Heavy Censoring 下载免费PDF全文
Antti Mikkelä Jukka Ranta Manuel González Marjaana Hakkinen Pirkko Tuominen 《Risk analysis》2016,36(11):2065-2080
A Bayesian statistical temporal‐prevalence‐concentration model (TPCM) was built to assess the prevalence and concentration of pathogenic campylobacter species in batches of fresh chicken and turkey meat at retail. The data set was collected from Finnish grocery stores in all the seasons of the year. Observations at low concentration levels are often censored due to the limit of determination of the microbiological methods. This model utilized the potential of Bayesian methods to borrow strength from related samples in order to perform under heavy censoring. In this extreme case the majority of the observed batch‐specific concentrations was below the limit of determination. The hierarchical structure was included in the model in order to take into account the within‐batch and between‐batch variability, which may have a significant impact on the sample outcome depending on the sampling plan. Temporal changes in the prevalence of campylobacter were modeled using a Markovian time series. The proposed model is adaptable for other pathogens if the same type of data set is available. The computation of the model was performed using OpenBUGS software. 相似文献
232.
In this article, a new attributes double sampling plan for three-class products (ADSPTP) is presented, and the corresponding operating characteristic function is constructed based on the given procedure of performing ADSPTP. Average sample numbers (ASN) for complete inspection and curtailed inspection of the second sample are derived and the extreme point is discussed on the three-dimensional ASN surface. In addition, the differences arising from different parameters are studied. Sampling plans are designed by a nonlinear optimization model. Finally, numerical examples and discussions are given to illustrate the obtained results, and tables of the designed plans under various conditions are provided. 相似文献
233.
企业知识产权包括商标、专利和著作权等,它是企业重要的无形资产。目前,国内大多数企业还不够重视企业的知识产权保护,尤其是专利保护。在研发过程中的专利申请及保护不及时、不到位,导致企业从项目研发到市场占有的整个过程蒙受巨大风险。从知识产权保护角度,探讨了企业研发过程中有关风险的防范措施。 相似文献
234.
《统计学通讯:模拟与计算》2012,41(6):776-786
In this article, we calibrate the Vasicek interest rate model under the risk neutral measure by learning the model parameters using Gaussian processes for machine learning regression. The calibration is done by maximizing the likelihood of zero coupon bond log prices, using mean and covariance functions computed analytically, as well as likelihood derivatives with respect to the parameters. The maximization method used is the conjugate gradients. The only prices needed for calibration are zero coupon bond prices and the parameters are directly obtained in the arbitrage free risk neutral measure. 相似文献
235.
《Journal of Social Work Practice》2012,26(2):165-183
There is a significant body of research into the benefits of animal-assisted therapy (AAT) but less into the fields known as equine-assisted learning and therapy (EAL/EAT) where horses are incorporated in therapeutic and learning interventions. This paper explores the experiences of seven ‘at-risk’ young people who participated in a therapeutic horsemanship (TH) programme. The study followed a practice-near approach seeking to capture the young people's experiences within a participative ethnography. Themes related to the risk and resilience literature such as self-confidence, self-esteem, self-efficacy and a sense of mastery, empathy and the opening of positive opportunities are explored in this paper. 相似文献
236.
Perception of Climate Risk among Rural Farmers in Vietnam: Consistency within Households and with the Empirical Record 下载免费PDF全文
Rural farmers in Vietnamese communes perceive climate risk and potential impacts on livelihood within a complex context that may influence individual and household decisions. In a primary survey of 1,145 residents of the Thach Ha district of Ha Tinh province, we gathered data regarding perception about stability in climate, potential risks to livelihood, demographic characteristics, orientation toward risk, and interest in expanding economic activity. Temporal analysis of meteorological and economic indicator data forms an empirical basis for comparison with human perception. We ask the basic question: Are rural farmers’ perceptions of climate consistent with the historical record and reproducible within households? We find that respondents do perceive climate anomalies, with some anchoring on recent extreme events as revealed by climate observational data, and further that spouses disproportionately share perceptions relative to randomly simulated pairings. To put climate‐related risk perception in a larger context, we examine patterns across a range of risks to livelihood faced by farmers (livestock disease, pests, markets, health), using dimension reduction techniques. We find that our respondents distinguish among potential causes of low economic productivity, with substantial emphasis on climate‐related impacts. They do not express uniform concern across risks, but rather average patterns reveal common modes and distinguish climate concern. Still, among those expressing concern about climate‐related risks to livelihood we do not find an association with expressed intention to pursue changes in economic activity as a risk management response. 相似文献
237.
以2007—2014年发生的我国A股上市公司参股非上市金融公司事件作为研究样本,对企业退出产融结合的现象进行了探讨,实证结果表明:每股收益越低、资产负债率越高、协同费用率越高、产融结合年限越短,企业越有可能退出产融结合。研究能帮助企业在实施产融结合后更有针对性地关注自身运营状况和财务状况,也为其建立健全风险监督与防范机制提供了一定的政策支持。 相似文献
238.
当代人尤其是青年人面临诸多现实世界中自我难以解决的矛盾和困惑时,期许能在电子"伊甸园"中找回自我价值和精神皈依。然而,虚拟空间并非想象中的天堂,类似"面具"的交流形式遮蔽着许多本真的存在,消解了现实世界的核心价值;游离在虚拟和现实之间的自我与社会脱离;对网络的过渡依赖性导致人格的异化;方向感的迷茫和自我定位的偏差,使得价值追求从崇高滑向流俗甚至恶俗。数字化生存方式正颠覆着传统生活方式和现实生活世界的诸多价值标准,而信息崇拜的推波助澜,更使人们产生了一种莫名的幸福被剥夺的感觉。 相似文献
239.
曲鹏飞 《沈阳工业大学学报(社会科学版)》2014,7(5):412-416
中国长期受到自然灾害的困扰,建立适合国情的巨灾保险体制已经成为必然。分析中国巨灾保险在供给和需求两方面均呈现不足状态的原因,借鉴国际上巨灾保险体制发展较好国家的经验,认为建立完善的巨灾保险体制需要从建立完备的法律体系、发展繁荣的巨灾保险市场和培养多层次的巨灾风险管理体系几个方面入手。从目前情况来看,应该从建立完善的法律体系、发展再保险市场、建立巨灾风险基金和发展政府巨灾债券几个方面着手,建设多层次的、适合中国国情的巨灾保险体制。 相似文献
240.
Chris M. R. Smerecnik Ilse Mesters Math J. J. M. Candel Hein De Vries Nanne K. De Vries 《Risk analysis》2012,32(1):54-66
The role of information processing in understanding people's responses to risk information has recently received substantial attention. One limitation of this research concerns the unavailability of a validated questionnaire of information processing. This article presents two studies in which we describe the development and validation of the Information‐Processing Questionnaire to meet that need. Study 1 describes the development and initial validation of the questionnaire. Participants were randomized to either a systematic processing or a heuristic processing condition after which they completed a manipulation check and the initial 15‐item questionnaire and again two weeks later. The questionnaire was subjected to factor reliability and validity analyses on both measurement times for purposes of cross‐validation of the results. A two‐factor solution was observed representing a systematic processing and a heuristic processing subscale. The resulting scale showed good reliability and validity, with the systematic condition scoring significantly higher on the systematic subscale and the heuristic processing condition significantly higher on the heuristic subscale. Study 2 sought to further validate the questionnaire in a field study. Results of the second study corresponded with those of Study 1 and provided further evidence of the validity of the Information‐Processing Questionnaire. The availability of this information‐processing scale will be a valuable asset for future research and may provide researchers with new research opportunities. 相似文献