Modeling Social Processes: Some Lessons from Sports

Sports events can provide helpful models for thinking about social processes. DiMaggio's hitting streak in baseball, for example, raises serious questions about how the causes of relatively uncommon social events are typically studied. The hitting streak also directs our attention to considering models that generate a distribution of outcomes in a population of social units. The series of games leading to a football championship is relevant for approaching the role of complex chains of events in leading to a given outcome (where each individual sequence itself has a low probability of occurring). A model of changing templates suggests a more realistic way of thinking about the linkages over time from an initial starting point to a given outcome. Another sports example, based on the application of a binomial model to the outcome of a series of games, suggests that we should think of chance as a dependent variable that is influenced by—among other factors—the nature of the social structure. Also examined are the special problems in explaining any specific outcome.     

基于证据推理和广义Shapley值的扩展概率语言多属性群决策方法

扩展概率语言词集通过语言变量概率分布的调整能够转化为多种语言信息表示模型,是语言变量、不确定语言信息、扩展犹豫模糊语言词集、分布语言评估信息、概率语言词集等的一般化,具有较强的通用性和实用性,是处理不确定性信息的重要工具。鉴于此,本文针对扩展概率语言环境下的多属性群决策问题,提出基于证据推理和广义Shapley值的多属性群决策方法。首先,提出扩展概率语言词集的定义和相关基础理论。其次,将广义Shapley值和证据推理相结合用于专家信息融合,并将广义Shapley值和TODIM方法相结合用于备选方案排序。再次,提出基于灰色关联法的权重确定模型来处理专家/属性权重部分未知的情况。最后,以绿色供应商选择为例进行分析,通过对比分析验证所提方法的有效性和优越性。     

A Flexible Hierarchical Bayesian Modeling Technique for Risk Analysis of Major Accidents

Safety analysis of rare events with potentially catastrophic consequences is challenged by data scarcity and uncertainty. Traditional causation‐based approaches, such as fault tree and event tree (used to model rare event), suffer from a number of weaknesses. These include the static structure of the event causation, lack of event occurrence data, and need for reliable prior information. In this study, a new hierarchical Bayesian modeling based technique is proposed to overcome these drawbacks. The proposed technique can be used as a flexible technique for risk analysis of major accidents. It enables both forward and backward analysis in quantitative reasoning and the treatment of interdependence among the model parameters. Source‐to‐source variability in data sources is also taken into account through a robust probabilistic safety analysis. The applicability of the proposed technique has been demonstrated through a case study in marine and offshore industry.     

The Impact of Portfolio Location Uncertainty on Probabilistic Seismic Risk Analysis

Probabilistic seismic risk analysis is a well‐established method in the insurance industry for modeling portfolio losses from earthquake events. In this context, precise exposure locations are often unknown. However, so far, location uncertainty has not been in the focus of a large amount of research. In this article, we propose a novel framework for treatment of location uncertainty. As a case study, a large number of synthetic portfolios resembling typical real‐world cases were created. We investigate the effect of portfolio characteristics such as value distribution, portfolio size, or proportion of risk items with unknown coordinates on the variability of loss frequency estimations. The results indicate that due to loss aggregation effects and spatial hazard variability, location uncertainty in isolation and in conjunction with ground motion uncertainty can induce significant variability to probabilistic loss results, especially for portfolios with a small number of risks. After quantifying its effect, we conclude that location uncertainty should not be neglected when assessing probabilistic seismic risk, but should be treated stochastically and the resulting variability should be visualized and interpreted carefully.     

Material planning with uncertain product quality†

Traditional material requirement planning (MRP) is a system procedure to determine input quantities and ordering times to meet a specified demand in a deterministic framework. A variety of modifications to MRP have been proposed to incorporate different forms of uncertainty in production systems. In this paper, wc consider the case where the uncertainty is due to quality variations in the production process, and we develop an approach which links material planning with quality variations and control.     

Universal-deterministic and probabilistic hypotheses in operations management research: a discussion paper

Abstract

Based on Karl Popper’s approach to science, this conceptual article aims at promoting a discussion on important issues debated in the OM literature. Our focus is on the different types of hypotheses used in OM investigations and the implications of this for the formulation and testing of theory with an emphasis on case study research. Given that Popper’s methodology calls for an adequate testing of scientific propositions (universal-deterministic or probabilistic), we illustrate how case study research can be used to conduct a severe test of a scientific theory. It is also explained how case studies can be utilized to propose universal-deterministic hypotheses that should then be tested. Our investigation further discusses why it is important to clearly acknowledge the differences between the two types of hypotheses. Otherwise, inadequate research designs, deficient policy advice, and other similar problems, can arise. Topics for future research and discussion are also offered.     

Updating Parameters of the Chicken Processing Line Model

A mathematical model of chicken processing that quantitatively describes the transmission of Campylobacter on chicken carcasses from slaughter to chicken meat product has been developed in Nauta et al. (2005). This model was quantified with expert judgment. Recent availability of data allows updating parameters of the model to better describe processes observed in slaughterhouses. We propose Bayesian updating as a suitable technique to update expert judgment with microbiological data. Berrang and Dickens's data are used to demonstrate performance of this method in updating parameters of the chicken processing line model.     

基于消费者损失效用的概率销售策略研究

随着网络信息技术的迅猛发展，概率销售作为一种新颖的销售策略广泛应用于旅游业。在双寡头销售商竞争销售背景下，两销售商分别向损失中性和损失厌恶型消费者销售高档产品和概率产品（中低档产品打包成概率产品）。本文首先运用博弈方法建立了损失中性下的概率销售模型，揭示了产品质量对销售商策略的影响。考虑到消费者在购买概率产品后存在期望损失，我们进一步构建了损失厌恶下的概率销售模型，研究了期望损失对概率销售策略的影响。研究表明期望损失为概率销售商实施概率销售提供了可能性，同时可以增加概率销售商的利润，但可能会损害其竞争者的利益；销售商是否采用概率销售策略主要取决于消费者对购买损失和选择损失的敏感度。最后给出了数值应用结果及管理学启示。     

A Probabilistic Transmission Model to Assess Infection Risk from Mycobacterium Tuberculosis in Commercial Passenger Trains

The objective of this article is to characterize the risk of infection from airborne Mycobacterium tuberculosis bacilli exposure in commercial passenger trains based on a risk‐based probabilistic transmission modeling. We investigated the tuberculosis (TB) infection risks among commercial passengers by inhaled aerosol M. tuberculosis bacilli and quantify the patterns of TB transmission in Taiwan High Speed Rail (THSR). A deterministic Wells‐Riley mathematical model was used to account for the probability of infection risk from M. tuberculosis bacilli by linking the cough‐generated aerosol M. tuberculosis bacilli concentration and particle size distribution. We found that (i) the quantum generation rate of TB was estimated with a lognormal distribution of geometric mean (GM) of 54.29 and geometric standard deviation (GSD) of 3.05 quantum/h at particle size ≤ 5 μm and (ii) the basic reproduction numbers (R₀) were estimated to be 0.69 (0.06–6.79), 2.82 (0.32–20.97), and 2.31 (0.25–17.69) for business, standard, and nonreserved cabins, respectively. The results indicate that commercial passengers taking standard and nonreserved cabins had higher transmission risk than those in business cabins based on conservatism. Our results also reveal that even a brief exposure, as in the bronchoscopy cases, can also result in a transmission when the quantum generation rate is high. This study could contribute to a better understanding of the dynamics of TB transmission in commercial passenger trains by assessing the relationship between TB infectiousness, passenger mobility, and key model parameters such as seat occupancy, ventilation rate, and exposure duration.     

多标准决策表中发现概率规则的变精度粗糙集方法

用优势关系代替不可分辨关系,本文提出了一种可以从多标准决策表中获取概率规则的扩展变精度粗糙集模型,该模型能够处理多标准决策表中可能的不一相容性,获取由偏好对象组成的概率决策规则集,并导出事例决策系统的偏好模型。研究结果表明:基于优势关系,从多标准决策表中获取的最小概率规则集,使用的条件数量较少,且导出规则的数量较少、较强。