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21.
Jan Hayes Sarah Maslen Christina Scott-Young Janice Wong 《Journal of Risk Research》2018,21(9):1131-1145
AbstractBased on a survey of Australian engineers (n = 275) this paper examines the impact of personal liability considerations on engineering decision-making. Almost all respondents who make high-stakes decisions saw questions of liability as having both positive (90%) and negative (87%) impacts. Our analysis shows that awareness of personal liability acts to focus the attention of many engineers on the moral dimension of their work. However, it also encourages more expensive decision-making, inhibition of innovation and professional paralysis. We argue that while personal legal liability is a legitimate way to focus engineers’ attention on the potential impact of their work, a problem arises when decision-makers are held responsible for disasters over which they had little control. The focus then shifts to ‘defensive engineering’ practices that are aimed at limiting individual liability rather than disaster prevention. Legal processes that are seen to unfairly allocate blame do not encourage practices that support future disaster prevention. 相似文献
22.
Hanen Ben Salah Jan G. De Gooijer Ali Gannoun Mathieu Ribatet 《Financial Markets and Portfolio Management》2018,32(4):419-436
While univariate nonparametric estimation methods have been developed for estimating returns in mean-downside risk portfolio optimization, the problem of handling possible cross-correlations in a vector of asset returns has not been addressed in portfolio selection. We present a novel multivariate nonparametric portfolio optimization procedure using kernel-based estimators of the conditional mean and the conditional median. The method accounts for the covariance structure information from the full set of returns. We also provide two computational algorithms to implement the estimators. Via the analysis of 24 French stock market returns, we evaluate the in-sample and out-of-sample performance of both portfolio selection algorithms against optimal portfolios selected by classical and univariate nonparametric methods for three highly different time periods and different levels of expected return. By allowing for cross-correlations among returns, our results suggest that the proposed multivariate nonparametric method is a useful extension of standard univariate nonparametric portfolio selection approaches. 相似文献
23.
The construction of an importance density for partially non‐Gaussian state space models is crucial when simulation methods are used for likelihood evaluation, signal extraction, and forecasting. The method of efficient importance sampling is successful in this respect, but we show that it can be implemented in a computationally more efficient manner using standard Kalman filter and smoothing methods. Efficient importance sampling is generally applicable for a wide range of models, but it is typically a custom‐built procedure. For the class of partially non‐Gaussian state space models, we present a general method for efficient importance sampling. Our novel method makes the efficient importance sampling methodology more accessible because it does not require the computation of a (possibly) complicated density kernel that needs to be tracked for each time period. The new method is illustrated for a stochastic volatility model with a Student's t distribution. 相似文献
24.
Jan Osers Dipl-lng. 《R&D Management》1972,3(1):29-33
In the countries of Eastern Europe the financing of R & D represents a difficult problem in terms of economic scientific policy. In these countries it is not only a question of a simple apportionment of centrally-held financial means to subordinate institutions, but also one of supporting promising fields of science, protecting long-term and costly research programmes against risks and losses, and, above all, providing an incentive for R & D institutions to work out economically meaningful R & D results and translate them into economic practice. This last point is of particular importance in a system lacking a free market mechanism. A historical survey of the development of financing methods in the R & D field and of the numerous attempts to reform these methods will show the extent of the efforts made in Eastern Europe (whether successfully or not does not concern us here) to find an adequate solution to these problems. 相似文献
25.
Firms developing new products often face the challenge of making investment decisions under uncertain input–cost conditions due to the price volatilities of the materials they use. These decisions need to be made long before the final products are launched on the market. Therefore, firms that invest in the opportunity to switch materials in a timely manner will have the flexibility to react to material price changes and realize competitive advantages. However, volatile material prices may also cause a firm to delay investment. Using real‐options reasoning, this paper studies the influence of input‐cost fluctuations on the timing decision to start new product development (NPD) and thus create the follow‐on opportunity to later replace an existing product. A model that combines waiting and switching options to derive influencing factors of the flexibility value that triggers the investment is developed and tested on a sample of material substitution projects from manufacturing firms. The results show how price uncertainty of the new and the old material, their joint price development, the expected project duration, and competitive preemption are related to the propensity to delay the start of NPD. The findings provide new insights on how timing in adopting materials can be used to hedge exposure to volatile material prices. The insights are relevant for adopters and producers of new materials, as well as for policy makers who strive for supporting the diffusion of new materials. 相似文献
26.
In this article, we examine the role of institutional context, organizational structures and trade union strategies in tempering membership decline in the number of trade unions in Poland. Empirical data include membership statistics collected for NSZZ Solidarno?? and 54 affiliates of two other largest trade union confederations (OPZZ and FZZ) supplemented by semi‐structured interviews with union leaders. In a decentralized collective bargaining system in Poland, a centralized trade union confederation (NSZZ Solidarno??) can more easily shift resources to efficiently organize workers than decentralized confederations, OPZZ and FZZ, whose development is mostly driven by competing trade unions representing narrower occupational groups. In conclusion, this observation is put in a broader context of the debates about trade union renewal in Eastern Europe. 相似文献
27.
Jan Henrik Wosnitza 《Financial Markets and Portfolio Management》2017,31(4):469-489
Bond laddering is a popular fixed-income investment strategy. The main purpose of this paper is to develop a methodology for determining private investors’ most interest rate risk (IRR)-return-efficient investment horizon for bond ladders (BLs), which are virtually free of credit risk. Two IRR measures of a continuously rolling and homogenous BL (CRHBL) are analytically derived under the assumption that interest rates are martingales. The first measure is the modified duration, which assumes a flat term structure of interest rates. However, this assumption is not fully supported by the empirical data and, thus, an additional IRR measure is proposed. Under each of these two measures, the ratios between the annual return in excess of the demand deposit rate and IRR of CRHBLs with different investment horizons are calculated. As expected, CRHBLs with rather low IRR are most risk-return-efficient. The results for the theoretical CRHBLs also apply to “real-world” discrete BLs. Thus, the proposed methodology can help private investors construct IRR-return-efficient discrete BLs. 相似文献
28.
The business process management literature describes a multitude of approaches (e.g. imperative, declarative or event-driven) that each result in a different mix of process flexibility, compliance, effectiveness and efficiency. Although the use of a single approach over the process lifecycle is often assumed, transitions between approaches at different phases in the process lifecycle may also be considered. This article explores several business process strategies by analysing the approaches at different phases in the process lifecycle as well as the various transitions. 相似文献
29.
This paper investigates whether cannabis use leads to worse mental health. To do so, we account for common unobserved factors affecting mental health and cannabis consumption by modeling mental health jointly with the dynamics of cannabis use. Our main finding is that using cannabis increases the likelihood of mental health problems, with current use having a larger effect than past use. The estimates suggest a dose–response relationship between the frequency of recent cannabis use and the probability of currently experiencing a mental health problem. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
30.
Linde K.J. Van Bets Machiel A.J. Lamers Jan P.M. van Tatenhove 《Journal of Sustainable Tourism》2017,25(11):1583-1599
Collective self-governance is gaining attention in the literature for maintaining the quality of key attractions and promoting sustainable tourism. The long-term success of collective self-governance is dependent on both its internal organization and its embeddedness in external state and non-state regulations. This paper presents the marine community concept, consisting of a policy and a user community, as a framework for investigating the internal and external dynamics of collective self-governance and its ability to steer toward sustainable cruise tourism. As methodology, a case study design was chosen which was primarily studied by means of interviews with a spectrum of relevant actors concerning expedition cruise tourism at Svalbard. By applying the marine community to Svalbard expedition cruise tourism governance, we draw the following conclusions: (1) collective self-governance complements governmental regulation through access to knowledge, conflict resolution and rule-compliance based on disclosure, traceability and trust; (2) collective self-governance's increasing role in the policy community alienates the expedition crew from the user community; and (3) informational overflow by co-existence of collective self-governance and state-governance challenges sustainable cruise tourism. Collective self-governance would, therefore, benefit from reflection, especially regarding the role of the user community that functions as an intermediary between state and self-governance regulations. 相似文献