Search results for "Uncertainty"
showing 10 items of 1010 documents
Minimising value-at-risk in a portfolio optimisation problem using a multi-objective genetic algorithm
2011
[EN] In this paper, we develop a general framework for market risk optimisation that focuses on VaR. The reason for this choice is the complexity and problems associated with risk return optimisation (non-convex and non-differential objective function). Our purpose is to obtain VaR efficient frontiers using a multi-objective genetic algorithm (GA) and to show the potential utility of the algorithm to obtain efficient portfolios when the risk measure does not allow calculating an optimal solution. Furthermore, we measure differences between VaR efficient frontiers and variance efficient frontiers in VaR-return space and we evaluate out-sample capacity of portfolios on both bullish and bearis…
Statistical formats to optimize evidence-based decision making: A behavioral approach
2013
Abstract Statistical information is crucial for managerial decision making. The decision-making literature in psychology and mathematical cognition documents how different statistical formats can facilitate certain types of decisions. The present analysis is the first of its kind to assess the impact of statistical formats in the presentation of data from market research on both the optimality of market decisions and the time required to perform the decision-making process. An economic experiment provides the data for this study. The experiment presents statistical information in simple frequencies and relative frequencies using numerical and pictorial representations in the context of diff…
Influence of Time Pressure on the Outcome of Intercultural Commercial Negotiations
2016
ABSTRACTIt is essential, in commercial negotiations, to know how time pressure is expressed among customers and suppliers and which its effect on the outcomes of negotiation is. Must pressure be applied or not? In order to solve this question, 21 customer/supplier negotiation case studies were carried out (intercultural and intracultural). We have evidenced that an adequate time pressure, at low levels, produced outcomes that tend to be positive. Also, the national culture of the negotiators may influence the decision about using or not time pressure in these processes; especially when considering In-Group Collectivism and Uncertainty Avoidance dimensions.
Analyzing the Impact of Culture on Average Time Spent on Social Networking Sites
2014
The study examines the influence of national culture on national averages of time spent (ATS) visiting the largest social networking sites (SNSs): Facebook, Twitter, and LinkedIn. The analysis uses cultural dimensions adopted from both the works of Hofstede and Schwartz, while controlling for country e-readiness and median population age. The findings suggest that culture's influence may be moderated by the media richness and type of network focus of each SNS. Overall, in rich-media SNSs, egalitarianism positively impacts ATS. Individualism and masculinity only impact ATS on friendship-oriented SNSs. Additionally, uncertainty avoidance and intellectual autonomy only impact ATS on profession…
An effectual approach to executing dynamic capabilities under unexpected uncertainty
2022
This study investigates how business-to-business (B2B) firms navigate contexts of unexpected uncertainty. Building on the theories of effectuation and dynamic capabilities, the study develops a model that highlights how effectual decision-making logic is manifested in the activities B2B firms employ to sense and seize new opportunities and threats and transform existing business operations. The qualitative data were collected in two phases (before and after the COVID-19 outbreak) and consisted of 24 interviews with 13 B2B firms. The findings demonstrate a strong reliance on managers' effectual decision-making in situations of unexpected uncertainty and provide a set of key activities that h…
L’affectif, les valeurs et le matching dans les choix des investisseurs individuels en incertitude : le cas de l’equity crowdfunding
2018
Our research focuses on the emotional and axiological determinants of investment choice in equity crowdfunding. We defend the thesis of a projects choice determined in part by the values and emotions of the individual investor. Our literature review is transversal to several fields of social sciences. Thus, the established theoretical framework articulates finance, marketing, HRM and psychology. An explanatory model using structural equations is proposed and tested empirically using data from a laboratory experiment. Our results confirm that values and interest in the project, an affective variable, have a significant effect on investor choices and dominate analytical judgment in the absenc…
Sensitivity analysis and uncertainty assessment of a SMBR model
2008
Over the last decade new technologies are emerging even more for wastewater treatment. Among the new technologies, a recent possible solution regards membrane bioreactors (MBRs) that represent a promising alternative to conventional processes. Nowadays, the recurrence to mathematical models as reliable tools in planning as well as management issues is of growing interest in Wastewater Treatment Plants field. Regarding MBR modelling, due to the intrinsic complexity and uncertainty in some processes, basic models that can provide a holistic understanding of the technology at a fundamental level are of great necessity. Many mathematical models have been developed for modelling the MBR which ba…
A Simple Indicator Based Evolutionary Algorithm for Set-Based Minmax Robustness
2018
For multiobjective optimization problems with uncertain parameters in the objective functions, different variants of minmax robustness concepts have been defined in the literature. The idea of minmax robustness is to optimize in the worst case such that the solutions have the best objective function values even when the worst case happens. However, the computation of the minmax robust Pareto optimal solutions remains challenging. This paper proposes a simple indicator based evolutionary algorithm for robustness (SIBEA-R) to address this challenge by computing a set of non-dominated set-based minmax robust solutions. In SIBEA-R, we consider the set of objective function values in the worst c…
Complementary Judgment Matrix Method with Imprecise Information for Multicriteria Decision-Making
2018
The complementary judgment matrix (CJM) method is an MCDA (multicriteria decision aiding) method based on pairwise comparisons. As in AHP, the decision-maker (DM) can specify his/her preferences using pairwise comparisons, both between different criteria and between different alternatives with respect to each criterion. The DM specifies his/her preferences by allocating two nonnegative comparison values so that their sum is 1. We measure and pinpoint possible inconsistency by inconsistency errors. We also compare the consistency of CJM and AHP trough simulation. Because preference judgments are always more or less imprecise or uncertain, we introduce a way to represent the uncertainty throu…
Inventory Control Under Parametric Uncertainty of Underlying Models
2013
A large number of problems in inventory control, production planning and scheduling, location, transportation, finance, and engineering design require that decisions be made in the presence of uncertainty of underlying models. In the present paper we consider the case, where it is known that the underlying distribution belongs to a parametric family of distributions. The problem of determining an optimal decision rule in the absence of complete information about the underlying distribution, i.e., when we specify only the functional form of the distribution and leave some or all of its parameters unspecified, is seen to be a standard problem of statistical estimation. Unfortunately, the clas…