Managing business portfolios in German companies

This study analyzes the behavior of top managers in managing their firms' business portfolios. A review of the existing literature provides a conceptual framework for a research design combining quantitative and qualitative techniques. Data were collected through interviews with 35 top managers of well-known German business firms and the findings of this study translated into guidelines for managers. The results suggest that successful top managers should be concerned with the social relationships and management processes within the corporate office, as well as with their use of management concepts in managing the business portfolio.     

Quality costing: a management review

This paper relates a review of the English language literature on quality costing and traces its historical development; it provides authoritative reading on the subject. The review also has a focus on collection and use of quality-costing methods, quantitative cost data and the role and views of accountants in the task of quality-cost collection and reporting. Amongst the main findings is the preoccupation with the prevention – appraisal – failure categorization of quality costs and lack of guidance on definitions. The considerable impact of the American quality profession on the development of quality costing is pointed out along with the increasingly positive stance of accountants.     

The Job Demand-Control (-Support) Model and psychological well-being: a review of 20 years of empirical research

The Job Demand-Control (JDC) model (Karasek, 1979) and the Job Demand-Control-Support (JDCS) model (Johnson, and Hall, 1988) have dominated research on occupational stress in the last 20 years. This detailed narrative review focuses on the JDC(S) model in relation to psychological well-being. It covers research from 63 samples, published in the period 1979-1997. In the review a distinction is drawn between two different hypotheses prevailing in research on the models. According to the strain hypothesis of the JDC model, employees working in a high-strain job (high demands-low control) experience the lowest well-being. The buffer hypothesis states that control can moderate the negative effects of high demands on well-being. Translating these hypotheses to the expanded JDCS model, the iso-strain hypothesis predicts the most negative outcomes among workers in an iso-strain job (high demands-low control-low social support/isolation), whereas the buffer hypothesis states that social support can moderate the negative impact of high strain on well-being. Although the literature gives considerable support for the strain and iso-strain hypotheses, support for the moderating influence of job control and social support is less consistent. The conceptualization of demands and control is a key factor in discriminating supportive from nonsupportive studies. Only aspects of job control that correspond to the specific demands of a given job moderate the impact of high demands on well-being. Furthermore, certain subpopulations appear to be more vulnerable to high (iso)strain, whereas others benefit more from high control. On the basis of the results of this review, suggestions for future research and theoretical development are formulated.     

Designing optimal food safety monitoring schemes using Bayesian network and integer programming: The case of monitoring dioxins and DL-PCBs

Efficient food safety monitoring should achieve optimal resource allocation. In this article, a methodology is presented to optimize the use of resources for food safety monitoring aimed at identifying noncompliant samples and estimating background level of hazards in food products. A Bayesian network (BN) model and an optimization model were combined in a single framework. The framework was applied to monitoring dioxins and dioxin-like polychlorinated biphenyls (DL-PCBs) in primary animal-derived food products in the Netherlands. The BN model was built using a national dataset with monitoring results of dioxins and DL-PCBs in animal-derived food products over a 10-year period (2008–2017). These data were used to estimate the probability of detecting suspect samples with dioxins and DL-PCBs levels above preset thresholds, given certain sample conditions. The results of the BN model were then inserted into the optimization model to compute an optimal monitoring scheme. Model estimates showed that the probability of dioxins and DL-PCBs exceeding threshold limits was higher in laying hen eggs and sheep meat than in other animal-derived food (except deer meat). Compared with the monitoring scheme used in the Netherlands in 2018, the optimal monitoring scheme would save around 10,000 EUR per year. This could be obtained by reallocating monitoring resources from products with lower probability of dioxin and DL-PCBs exceeding threshold limits (e.g., pig meat) to products with higher probability (e.g., bovine animal meat), and by shifting sample collection from the last quarter of the year toward the first three quarters of the year.     

Children’s Recognition and Discrimination of Fear and Disgust Facial Expressions

Facial expressions of fear and disgust have repeatedly been found to be less well recognized than those of other basic emotions by children. We undertook two studies in which we investigated the recognition and visual discrimination of these expressions in school-age children. In Study 1, children (5, 6, 9, and 10 years of age) were shown pairs of facial expressions, and asked to tell which one depicted a target emotion. The results indicated that accuracy in 9- and 10-year-olds was higher than in 5- and 6-year-olds for three contrasts: disgust–anger, fear–surprise, and fear–sadness. Younger children had more difficulty recognizing disgust when it was presented along with anger, and in recognizing fear when it was presented along with surprise. In Study 2, children (5, 6, 9, and 10 years of age) were shown a target expression along with two other expressions, and were asked to point to the expression that was the most similar to the target. Contrary to our expectations, even 5- and 6-year-olds were very accurate in discriminating fear and disgust from the other emotions, suggesting that visual perception was not the main limiting factor for the recognition of these emotions in school-age children.     

NUSAP Method for Evaluating the Data Quality in a Quantitative Microbial Risk Assessment Model for Salmonella in the Pork Production Chain

The numeral unit spread assessment pedigree (NUSAP) system was implemented to evaluate the quality of input parameters in a quantitative microbial risk assessment (QMRA) model for Salmonella spp. in minced pork meat. The input parameters were grouped according to four successive exposure pathways: (1) primary production (2) transport, holding, and slaughterhouse, (3) postprocessing, distribution, and storage, and (4) preparation and consumption. An inventory of 101 potential input parameters was used for building the QMRA model. The characteristics of each parameter were defined using a standardized procedure to assess (1) the source of information, (2) the sampling methodology and sample size, and (3) the distributional properties of the estimate. Each parameter was scored by a panel of experts using a pedigree matrix containing four criteria (proxy, empirical basis, method, and validation) to assess the quality, and this was graphically represented by means of kite diagrams. The parameters obtained significantly lower scores for the validation criterion as compared with the other criteria. Overall strengths of parameters related to the primary production module were significantly stronger compared to the other modules (the transport, holding, and slaughterhouse module, the processing, distribution, and storage module, and the preparation and consumption module). The pedigree assessment contributed to select 20 parameters, which were subsequently introduced in the QMRA model. The NUSAP methodology and kite diagrams are objective tools to discuss and visualize the quality of the parameters in a structured way. These two tools can be used in the selection procedure of input parameters for a QMRA, and can lead to a more transparent quality assurance in the QMRA.     

Nonparametric Identification of Risk Aversion in First‐Price Auctions Under Exclusion Restrictions

This paper studies the nonparametric identification of the first‐price auction model with risk averse bidders within the private value paradigm. First, we show that the benchmark model is nonindentified from observed bids. We also derive the restrictions imposed by the model on observables and show that these restrictions are weak. Second, we establish the nonparametric identification of the bidders' utility function under exclusion restrictions. Our primary exclusion restriction takes the form of an exogenous bidders' participation, leading to a latent distribution of private values that is independent of the number of bidders. The key idea is to exploit the property that the bid distribution varies with the number of bidders while the private value distribution does not. We then extend these results to endogenous bidders' participation when the exclusion restriction takes the form of instruments that do not affect the bidders' private value distribution. Though derived for a benchmark model, our results extend to more general cases such as a binding reserve price, affiliated private values, and asymmetric bidders. Last, possible estimation methods are proposed.     

大龄未婚男性流动人口的风险性行为及影响因素

以西安市28岁以上的大龄未婚男性流动人口为研究对象,进行了性行为相关内容的电子问卷调查,并收集农村大龄未婚男性进入城市后可能产生的风险性行为信息;通过分析明确了大龄未婚男性流动人口的风险性行为概况和人群特征,用逻辑斯蒂(Logistic)回归模型探析了其行为现状与影响因素。研究发现,大龄未婚男性流动人口在多个性伴侣与商业性行为表现出明显倾向;大龄未婚男性流动人口的经济条件年龄以及受教育程度对其风险性行为产生了影响;周围人群的风险性行为参与对大龄未婚男性流动人口的风险性行为参与产生带动作用;此外,无保护性行为在这一人群中的比例已经显著降低。