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201.
A simulation study examines the impact of a simplification strategy that replaces distributional attribute evaluations with their expected values and uses those expectations in an additive value model. Several alternate simplified forms and approximation approaches are investigated, with results showing that in general the simplified models are able to provide acceptable performance that is fairly robust to a variety of internal and external environmental changes, including changes to the distributional forms of the attribute evaluations, errors in the assessment of the expected values, and problem size. Certain of the simplified models are shown to be highly sensitive to the form of the underlying preference functions, and in particular to extreme non-linearity in these preferences. 相似文献
202.
Researchers have long recognized that subjective perceptions of risk are better predictors of choices over risky outcomes than science‐based or experts’ assessments of risk. More recent work suggests that uncertainty about risks also plays a role in predicting choices and behavior. In this article, we develop and estimate a formal model for an individual's perceived health risks associated with arsenic contamination of his or her drinking water. The modeling approach treats risk as a random variable, with an estimable probability distribution whose variance reflects uncertainty. The model we estimate uses data collected from a survey given to a sample of people living in arsenic‐prone areas in the United States. The findings from this article support the fact that scientific information is essential to explaining the mortality rate perceived by the individuals, but uncertainty about the probability remains significant. 相似文献
203.
We consider the scheduling of truck arrivals at an air cargo terminal. By coordinating arrivals of cargo delivery trucks with outbound flight departure schedules, some of the shipments can be transferred directly to the departing flights, while others will be stored at the terminal's storage facility and incur extra handling and storage costs. The objective is to obtain a feasible schedule so as to minimize the total cost of operations. We formulate the problem as a time‐indexed integer program and show that, even with limited number of unloading docks at the terminal, the problem is non‐trivial (NP‐hard in the strong sense). Our solution method includes an exact solution procedure to determine an optimal unloading sequence for the shipments carried by each truck, together with a Lagrangian relaxation‐based heuristic for assigning trucks to truck docks and determining truck arrival times. We conducted computational experiments to test the performance of our solution method. Computational results show that our method can generate near‐optimal solutions efficiently. Our simulation results indicate that the scheduling approach proposed in this paper has the potential to generate significant cost savings over a first‐come, first‐served approach currently used at the air cargo terminal that we observed. 相似文献
204.
N. Nisan Selekler-Goksen Özlem Yildirim Öktem 《Journal of Management and Governance》2009,13(3):193-213
This longitudinal study investigates the impact of national and international pressures to improve corporate governance in an emerging economy from an institutional theory perspective. Recently, family business groups (FBGs), the dominant form of organizing in emerging economies, have been criticized by policy makers for their poor governance structures. A common recommendation to FBGs has been increasing the number of independent, outsider directors on their boards. Thus, change in the board compositions of the quoted subsidiaries of the six biggest FBGs is analyzed over 2002–2006. One-way-ANOVA and t-tests were used as statistical tools. Findings reveal that there has not been a statistically significant change in board compositions over the research period. FBGs were found to resist institutional pressures through ‘avoidance’, ‘defiance’ and “manipulation” strategies due to the absence of coercive pressures and multiple forms of ‘institutional work’ for change. 相似文献
205.
Information Asymmetries in the Hiring Process and the Risk of New Leader Dismissal: Insights from English Premier League Soccer Organizations 下载免费PDF全文
Why are some new leaders dismissed more quickly than others? Adopting agency theory logic, the authors examine how different succession contexts shape boards’ information asymmetries about a potential candidate's competencies in the hiring process, which influences the propensity of making poor hiring decisions and hence the risk of new leader dismissal. Employing duration analysis on a sample of 164 newly appointed leaders in the English premier league (1996–2014), the authors find that the risk of new leader dismissal is: (i) greater when the predecessor leader's exit was initiated by them rather than by the board; (ii) greater when following a longer‐tenured predecessor; and (iii) lower for outside successions compared with inside successions. 相似文献
206.
Vladimir Vanyushyn Maria Bengtsson Malin H. Näsholm Håkan Boter 《Review of Managerial Science》2018,12(2):535-557
International coopetition has rarely been studied in relation to innovation. Further exploration of effects of international coopetition, i.e. the pursuit of simultaneous cooperation and competition, on a firm’s innovation performance is especially important as such a relationship is challenging with a high propensity to fail. This observation formed the point of departure for this study, which aims to increase the understanding of the effects of international coopetition on firm innovativeness and how these effects are conditioned on the magnitude of the organizational adjustments a firm introduces. We use an unbalanced panel of 9839 firms that participated in four waves of the Swedish Community Innovation Survey between 2008 and 2014 as our empirical base. We illustrate that firms that cooperate with competitors internationally are more likely to exhibit higher propensity to introduce radical innovations, yet this effect is conditioned upon the magnitude of organizational adjustments. Overall, our study contributes to the understanding of the implications of international coopetition and what a firm needs to benefit from it. 相似文献
207.
Dimitris N. Trakas Mathaios Panteli Nikos D. Hatziargyriou Pierluigi Mancarella 《Risk analysis》2019,39(1):195-211
The increased frequency of extreme events in recent years highlights the emerging need for the development of methods that could contribute to the mitigation of the impact of such events on critical infrastructures, as well as boost their resilience against them. This article proposes an online spatial risk analysis capable of providing an indication of the evolving risk of power systems regions subject to extreme events. A Severity Risk Index (SRI) with the support of real‐time monitoring assesses the impact of the extreme events on the power system resilience, with application to the effect of windstorms on transmission networks. The index considers the spatial and temporal evolution of the extreme event, system operating conditions, and the degraded system performance during the event. SRI is based on probabilistic risk by condensing the probability and impact of possible failure scenarios while the event is spatially moving across a power system. Due to the large number of possible failures during an extreme event, a scenario generation and reduction algorithm is applied in order to reduce the computation time. SRI provides the operator with a probabilistic assessment that could lead to effective resilience‐based decisions for risk mitigation. The IEEE 24‐bus Reliability Test System has been used to demonstrate the effectiveness of the proposed online risk analysis, which was embedded in a sequential Monte Carlo simulation for capturing the spatiotemporal effects of extreme events and evaluating the effectiveness of the proposed method. 相似文献
208.
Michael A. L. Hayashi Marisa C. Eisenberg Joseph N. S. Eisenberg 《Risk analysis》2019,39(10):2214-2226
Achieving health gains from the U.N. Sustainable Development Goals of universal coverage for water and sanitation will require interventions that can be widely adopted and maintained. Effectiveness—how an intervention performs based on actual use—as opposed to efficacy will therefore be central to evaluations of new and existing interventions. Incomplete compliance—when people do not always use the intervention and are therefore exposed to contamination—is thought to be responsible for the lower‐than‐expected risk reductions observed from water, sanitation, and hygiene interventions based on their efficacy at removing pathogens. We explicitly incorporated decision theory into a quantitative microbial risk assessment model. Specifically, we assume that the usability of household water treatment (HWT) devices (filters and chlorine) decreases as they become more efficacious due to issues such as taste or flow rates. Simulations were run to examine the tradeoff between device efficacy and usability. For most situations, HWT interventions that trade lower efficacy (i.e., remove less pathogens) for higher compliance (i.e., better usability) contribute substantial reductions in diarrheal disease risk compared to devices meeting current World Health Organization efficacy guidelines. Recommendations that take into account both the behavioral and microbiological properties of treatment devices are likely to be more effective at reducing the burden of diarrheal disease than current standards that only consider efficacy. 相似文献
209.
We propose that the purposeful sharing of strategic decisions and the process of making and taking those between the dominant coalition of an organization (Strategic Shared Leadership or SSL thereafter), initiated and supported by a focal strategic leader or small team, engenders Organizational Dynamic Capabilities (ODCs) though the transfer of individually-residing DCs within the SSL team, the transformation -co-creation of novel ones and their embeddedness-institutionalization within the organization. It also enhances organizational cognition which mediates the relationship by enriching co-created ODCs and their capacity to deliver reliably change through sensing, seizing and reconfiguring. Accordingly, SSL serves as a co-creator and key predictor of the emergence of ODCs. This helps address the challenges of DCs to marry stability with change, be predictable and to be capable of predicting. 相似文献
210.
Yilin Shen Thang N. Dinh My T. Thai Hien T. Nguyen 《Journal of Combinatorial Optimization》2014,28(1):186-217
As an imperative channel for fast information propagation, online social networks (OSNs) also have their defects. One of them is the information leakage, i.e., information could be spread via OSNs to the users whom we are not willing to share with. Thus the problem of constructing a circle of trust to share information with as many friends as possible without further spreading it to unwanted targets has become a challenging research topic but still remained open. Our work is the first attempt to study the Maximum Circle of Trust problem seeking to share the information with the maximum expected number of poster’s friends such that the information spread to the unwanted targets is brought to its knees. First, we consider a special and more practical case with the two-hop information propagation and a single unwanted target. In this case, we show that this problem is NP-hard, which denies the existence of an exact polynomial-time algorithm. We thus propose a Fully Polynomial-Time Approximation Scheme (FPTAS), which can not only adjust any allowable performance error bound but also run in polynomial time with both the input size and allowed error. FPTAS is the best approximation solution one can ever wish for an NP-hard problem. We next consider the number of unwanted targets is bounded and prove that there does not exist an FPTAS in this case. Instead, we design a Polynomial-Time Approximation Scheme (PTAS) in which the allowable error can also be controlled. When the number of unwanted targets are not bounded, we provide a randomized algorithm, along with the analytical theoretical bound and inapproximaibility result. Finally, we consider a general case with many hops information propagation and further show its #P-hardness and propose an effective Iterative Circle of Trust Detection (ICTD) algorithm based on a novel greedy function. An extensive experiment on various real-world OSNs has validated the effectiveness of our proposed approximation and ICTD algorithms. Such an extensive experiment also highlights several important observations on information leakage which help to sharpen the security of OSNs in the future. 相似文献