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41.
As flood risks grow worldwide, a well‐designed insurance program engaging various stakeholders becomes a vital instrument in flood risk management. The main challenge concerns the applicability of standard approaches for calculating insurance premiums of rare catastrophic losses. This article focuses on the design of a flood‐loss‐sharing program involving private insurance based on location‐specific exposures. The analysis is guided by a developed integrated catastrophe risk management (ICRM) model consisting of a GIS‐based flood model and a stochastic optimization procedure with respect to location‐specific risk exposures. To achieve the stability and robustness of the program towards floods with various recurrences, the ICRM uses stochastic optimization procedure, which relies on quantile‐related risk functions of a systemic insolvency involving overpayments and underpayments of the stakeholders. Two alternative ways of calculating insurance premiums are compared: the robust derived with the ICRM and the traditional average annual loss approach. The applicability of the proposed model is illustrated in a case study of a Rotterdam area outside the main flood protection system in the Netherlands. Our numerical experiments demonstrate essential advantages of the robust premiums, namely, that they: (1) guarantee the program's solvency under all relevant flood scenarios rather than one average event; (2) establish a tradeoff between the security of the program and the welfare of locations; and (3) decrease the need for other risk transfer and risk reduction measures.  相似文献   
42.
The objective of meat inspection is to promote animal and public health by preventing, detecting, and controlling hazards originating from animals. With the improvements of sanitary level in pig herds, the hazards profile has shifted and the inspection procedures no longer target major foodborne pathogens (i.e., not risk based). Additionally, carcass manipulations performed when searching for macroscopic lesions can lead to cross‐contamination. We therefore developed a stochastic model to quantitatively describe cross‐contamination when consecutive carcasses are submitted to classic inspection procedures. The microbial hazard used to illustrate the model was Salmonella, the data set was obtained from Brazilian slaughterhouses, and some simplifying assumptions were made. The model predicted that due to cross‐contamination during inspection, the prevalence of contaminated carcass surfaces increased from 1.2% to 95.7%, whereas the mean contamination on contaminated surfaces decreased from 1 logCFU/cm² to ?0.87 logCFU/cm², and the standard deviations decreased from 0.65 to 0.19. These results are explained by the fact that, due to carcass manipulations with hands, knives, and hooks, including the cutting of contaminated lymph nodes, Salmonella is transferred to previously uncontaminated carcasses, but in small quantities. These small quantities can easily go undetected during sampling. Sensitivity analyses gave insight into the model performance and showed that the touching and cutting of lymph nodes during inspection can be an important source of carcass contamination. The model can serve as a tool to support discussions on the modernization of pig carcass inspection.  相似文献   
43.
44.
In this paper, we study the impact of macro- and micro-economic uncertainty on family formation between 1970 and 2000 in The Netherlands. Using data of the Family Survey Dutch Population, we analysed the monthly hazard rates of experiencing the transition into first union, first marriage and parenthood after the start of the relationship of 365 male and 364 female partners by applying piecewise-constant exponential models. The results show that macro-economic uncertainties, i.e. high unemployment rates, lead to postponement of the first union and marriage, but not of the first child. In addition, we found that this relationship is not interpreted by individual-level employment insecurity, i.e. temporary employment or unemployment, which does not seem to prevent people from making long-term family commitments. Although hypothesized, we did not find that the negative effects of macro- and micro-level insecurities on family formation reinforce each other or that they vary between individuals with different educational qualifications.  相似文献   
45.
In analyzing data from unreplicated factorial designs, the half-normal probability plot is commonly used to screen for the ‘vital few’ effects. Recently, many formal methods have been proposed to overcome the subjectivity of this plot. Lawson (1998) (hereafter denoted as LGB) suggested a hybrid method based on the half-normal probability plot, which is a blend of Lenth (1989) and Loh (1992) method. The method consists of fitting a simple least squares line to the inliers, which are determined by the Lenth method. The effects exceeding the prediction limits based on the fitted line are candidates for the vital few effects. To improve the accuracy of partitioning the effects into inliers and outliers, we propose a modified LGB method (hereafter denoted as the Mod_LGB method), in which more outliers can be classified by using both the Carling’s modification of the box plot (Carling, 2000) and Lenth method. If no outlier exists or there is a wide range in the inliers as determined by the Lenth method, more outliers can be found by the Carling method. A simulation study is conducted in unreplicated 24 designs with the number of active effects ranging from 1 to 6 to compare the efficiency of the Lenth method, original LGB methods, and the proposed modified version of the LGB method.  相似文献   
46.
The recently developed rolling year GEKS procedure makes maximum use of all matches in the data to construct nonrevisable price indexes that are approximately free from chain drift. A potential weakness is that unmatched items are ignored. In this article we use imputation Törnqvist price indexes as inputs into the rolling year GEKS procedure. These indexes account for quality changes by imputing the “missing prices” associated with new and disappearing items. Three imputation methods are discussed. The first method makes explicit imputations using a hedonic regression model which is estimated for each time period. The other two methods make implicit imputations; they are based on time dummy hedonic and time-product dummy regression models and are estimated on bilateral pooled data. We present empirical evidence for New Zealand from scanner data on eight consumer electronics products and find that accounting for quality change can make a substantial difference.  相似文献   
47.
In Brazil, the age and education compositions of the male labor force is changing with great regional variation. Based on Demographic Census microdata, results indicate that cohort size has a negative impact on earnings, but this effect is decreasing over time. In this study we consider the impact on earnings by age and education, as well as estimated income inequality reduction and racial differentials. Fertility decline and improve regarding educational attainment had a significant influence on the decline of income inequality in the country. Moreover, the non-white population has been experiencing less success in relation to educational achievement, compared to the white population.  相似文献   
48.
Sexual satisfaction is an important indicator of sexual health and is strongly associated with relationship satisfaction. However, research exploring lay definitions of sexual satisfaction has been scarce. We present thematic analysis of written responses of 449 women and 311 men to the question “How would you define sexual satisfaction?” The participants were heterosexual individuals with a mean age of 36.05 years (SD = 8.34) involved in a committed exclusive relationship. In this exploratory study, two main themes were identified: personal sexual well-being and dyadic processes. The first theme focuses on the positive aspects of individual sexual experience, such as pleasure, positive feelings, arousal, sexual openness, and orgasm. The second theme emphasizes relational dimensions, such as mutuality, romance, expression of feelings, creativity, acting out desires, and frequency of sexual activity. Our results highlight that mutual pleasure is a crucial component of sexual satisfaction and that sexual satisfaction derives from positive sexual experiences and not from the absence of conflict or dysfunction. The findings support definitions and models of sexual satisfaction that focus on positive sexual outcomes and the use of measures that incorporate items linked to personal and dyadic sexual rewards for both men and women.  相似文献   
49.
Housing recovery is an unequal and complex process presumed to occur in four stages: emergency shelter, temporary shelter, temporary housing, and permanent housing. This work questions the four-stage typology and examines how different types of shelter align with multiple housing recovery stages given different levels of social vulnerability. This article also presents a Markov chain model of the postdisaster housing recovery process that focuses on the experience of the household. The model predicts the sequence and timing of a household going through housing recovery, capturing households that end in either permanent housing or a fifth possible stage of failure. The probability of a household transitioning through the stages is computed using a transition probability matrix (TPM). The TPM is assembled using proposed transition probability models that vary with the social vulnerability of the household. Monte Carlo techniques are applied to demonstrate the range of sequences and timing that households experience going through the housing recovery process. A set of computational rules are established for sending a household to the fifth stage, representing a household languishing in unstable housing. This predictive model is exemplified on a virtual community, Centerville, where following a severe earthquake scenario, differences in housing recovery times exceed four years. The Centerville analysis results in nearly 5% of households languishing in unstable housing, thereby failing to reach housing recovery. These findings highlight the disparate trajectories experienced by households with different levels of social vulnerability. Recommendations are provided at the end for more equitable postdisaster recovery policies.  相似文献   
50.
Sexual communication is a principal means of transmitting sexual values, beliefs, expectations, and knowledge from parents to children. Although this area has received considerable research attention, more studies with representative samples are needed to assure that findings are reflective of populations of interest. A nationally representative sample of parent–adolescent dyads (N = 2,965; mean adolescent age = 13.8 years) in the Netherlands was employed to examine the frequency of parent–adolescent sexual communication and its association with adolescent sexual behaviors (defined as sexual initiation, condom use, and contraceptive pill use). Nine communication topics in the areas of anatomy, relationships and rights, and protection and contraception were examined. In all, 75%of parents reported having discussed at least one topic multiple times with their adolescents. Romantic relationships were discussed most frequently. Hierarchical logistic regression analyses indicated that parent–adolescent sexual communication on protection and contraception was positively associated with adolescent sexual initiation and contraceptive pill use but not condom use. This may reflect that adolescents, when they become sexually active, are more likely to discuss sexuality with their parents. Findings are interpreted within the context of Dutch culture, which is generally accepting of adolescent sexuality and characterized by open sexual communication.  相似文献   
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