Comparing two territory partitions in districting problems: Indices and practical issues

Planning as part of public sector decision-making situations is an activity of critical importance, with direct relevance for urban planners. The ramifications of such decisions generally have significant effect on peoples’ lives. The current paper deals with the comparison between territorial maps in the context of districting problems with a strong socio-economic component. The theoretical problem involves the comparison of two partitions in a connected, undirected, and planar graph. In considering this problem, we introduce three new indices to compare territory partitions: compatibility, inclusion, and distance, all of which have importance for real-world planning situations. Numerical experiments of these indices were carried out for the communes network in (Iˆle de France), France.     

重构企业R＆D项目战略投资决策方法体系

传统的投资决策方法是一种建立在广泛应用的以货币的时间价值为基础的投资决策方法,它已越来越不能适应当今充满不确定性和竞争性的市场需要.实物期权方法比传统的折现现金流法（DCF）更适合来分析不确定条件下的投资决策问题,但仅凭实物期权方法还不能对不完全竞争环境下的企业R＆D项目战略投资问题进行准确分析和估价,而引入期权博弈理论恰好能克服这些缺陷.文章从理论上阐述了重构企业R＆D项目投资决策方法体系的可能性和必要性,并由此提出了研究的基本框架.     

Risk, uncertainty, and option exercise

Many economic decisions can be described as an option exercise or optimal stopping problem under uncertainty. Motivated by experimental evidence such as the Ellsberg Paradox, we follow Knight (1921) and distinguish risk from uncertainty. To capture this distinction, we adopt the multiple-priors utility model. We show that the impact of ambiguity on the option exercise decision depends on the relative degrees of ambiguity about continuation payoffs and termination payoffs. Consequently, ambiguity may accelerate or delay option exercise. We apply our results to investment and exit problems, and show that the myopic NPV rule can be optimal for an agent having an extremely high degree of ambiguity aversion.     

Incomplete markets, ambiguity, and irreversible investment

The problem of irreversible investment with idiosyncratic risk is studied by interpreting market incompleteness as a source of ambiguity over the appropriate no-arbitrage discount factor. The maxmin utility over multiple priors framework is used to model and solve the irreversible investment problem. Multiple priors are modeled using the notion of κ‐ignorance. This set-up is used to analyze finitely lived options. For infinitely lived options the notion of constant κ‐ignorance is introduced. For these sets of density generators the corresponding optimal stopping problem is solved for general (in-)finite horizon optimal stopping problems driven by geometric Brownian motion. It is argued that an increase in the set of priors delays investment, whereas an increase in the degree of market completeness can have a non-monotonic effect on investment.     

Making sustainable sourcing decisions: practical evidence from the automotive industry

Achieving environmental and sustainable performance within an organisation’s supply chain and manufacturing operations will be feasible if upstream supply partners have the same commitments in performing their operations in a sustainable manner. Given the debate above, we propose a comprehensive framework to address the sustainable supplier selection and order allocation (SSS&OA) problem. The framework developed is practical, that starts by using an audition check-list specific for each sustainability dimension (environmental, economic and social), from which the weighted values of its comprised criteria are obtained. The weighted scores of the selected sustainable suppliers are utilised by a proposed bi-objective order allocation model in order to make sourcing decisions. The strength of the proposed framework is its practical applicability to provide a solution for SSS&OA problems which is validated through a real-world application. Finally, research findings, theoretical and managerial insights and also directions for additional research are presented.     

Preserving employee capabilities in economic turbulence

This paper examines how, in times of austerity, employee capabilities can assist firms in augmenting their human capital and at the same time meeting their financial obligations. Real option theory, a concept borrowed from economics, is used to provide a theoretical framework to demonstrate that management has choices when making decisions in times of austerity. The framework provides a means of understanding how decisions can be made to both maintain employee capabilities and at the same time focus on company profit maximisation, typically demanded by shareholders in times of austerity. The study establishes the benefits of a continuous approach to capability development in an environment of economic turbulence. Most importantly, it paves the way for future research in this increasingly critical area.     

Optimizing large-scale emergency medical system operations on highways using the hypercube queuing model

In this study, we present a series of well-known optimization methods to address two related decisions associated with the design of large-scale ambulance operations on highways: (1) The question of location, and (2) the issue of districting. As a result of computer storage and runtime constraints, previous approaches have only considered small-to-moderate scale problem scenarios, generally employing exact hypercube queuing models integrated into optimization procedures. We overcome these limitations here by embedding a fast and accurate hypercube approximation algorithm adapted for partial backup dispatch policies in single- and multi-start greedy heuristics. The proposed methods are tested on small-to-large-scale problems involving up to 100 ambulances. The results suggest that our approach is a viable alternative for the analysis and configuration of large-scale highway emergency medical systems, providing reasonable accuracy and affordable run times.     

Contraction flexibility,operating leverage,and financial leverage

This study investigates the impacts of contraction flexibility and operating leverage on financial leverage from the perspective of the agency conflict between shareholders and debtholders. In a continuous-time real option framework, we demonstrate that shareholders’ contraction flexibility may have an adverse effect on financial leverage, and that the substitution relation between operating leverage and financial leverage is persistent or pronounced in the presence of contraction flexibility. The evidence from Chinese listed firms not only supports our theoretical predictions well, but also offers a method to examine the agency conflict hypothesis. We suggest that the high proportion of bank loans or long-term debt in total liabilities can help levered firms alleviate the agency problem arising from contraction decisions.     

Optimizing the credit term decisions in supply chain finance

We study a credit term determination problem in the context of a supplier-buyer supply chain. The supplier's credit term decision is simultaneously made with its production and inventory decisions, and most importantly, it is impacted by the buyer's order quantity. We present a new game-theoretic framework to model this problem, which captures the interaction between the supplier's credit term decision and the buyer's order decision in a multi-period setting. An exact method based on nonlinear programming is implemented to obtain the optimal solutions. We apply our methodologies on a real world case. The computational results show that our approach significantly outperforms the heuristics with fixed credit terms, and either a short or a long credit term can be sub-optimal for the supplier in profitability. Our work offers the first data-driven model and solution approach that assists purchasing and supply managers to make optimal dynamic credit term decision in conjunction with production, ordering and inventory decisions in a game-theoretic setting.     

Economies with a mean demand function

The present paper shows one way to look at G. Debreu and W. Hildenbrand's conjecture that certain atomless economies have mean demand functions. We conclude within the continuity framework that an economy gives rise ‘in general’ to a continuous mean demand function, and that the class of all atomless economies is ‘big’ in the space of all economies with a continuous mean demand function. The same problems are reconsidered within the framework of a space of differentiable preferences at the end.     

Heuristic estimates in shortest path algorithms

Shortest path problems occupy an important position in operations research as well as in artificial intelligence. In this paper we study shortest path algorithms that exploit heuristic estimates. The well-known algorithms are put into one framework. Besides, we present an interesting application of binary numbers in the shortest path theory.     

Why and how do firms reshore? A contingency-based conceptual framework

Much of the growing body of reshoring literature has focused on why firms reverse a prior location decision. While valuable, this work needs extending to how the decision to reshore is operationalised. Using a two-stage approach, this paper presents a conceptual framework that covers both why and how firms reshore. The framework also utilises contingency theory to identify the factors that influence these decisions. It is therefore claimed to be more comprehensive than others frameworks found in the literature. First, a systematic literature review deductively develops an initial framework. Second, a revised version of the framework is presented using evidence from a single, exemplar case of captive reshoring in the textiles industry. The case evidence identifies new factors and extends a typology of reshoring decisions proposed in the literature to more accurately reflect the dynamic, complex, and incremental nature of the onshore-offshore-reshore location and ownership decision.     

Optimal prepayment and default rules for mortgage-backed securities

We study the optimal stopping problems embedded in a typical mortgage. Despite a possible non-rational behaviour of the typical borrower of a mortgage, such problems are worth to be solved for the lender to hedge against the prepayment risk, and because many mortgage-backed securities pricing models incorporate this suboptimality via a so-called prepayment function which can depend, at time t, on whether the prepayment is optimal or not. We state the prepayment problem in the context of the optimal stopping theory and present an algorithm to solve the problem via weak convergence of computationally simple trees. Numerical results in the case of the Vasicek model and of the CIR model are also presented. The procedure is extended to the case when both the prepayment as well as the default are possible: in this case, we present a new method of building two-dimensional computationally simple trees, and we apply it to the optimal stopping problem.     

On the Optimal Structure of Government Subsidies for Enterprise Zones and Other Locational Development Programs

Government locational development programs often reward businesses for decisions they would have made or that are going to be quickly reversed. This paper presents a model to determine the amount and structure of government locational subsidies that minimize this problem. We model the firm's decision to switch locations as an option whose value depends on stochastic operating costs, the costs to switch locations and subsidies offered by the government. The government maximizes the expected benefit from the operation of the firm within its preferred location by choosing a subsidy package that explicitly and endogenously recognizes the firm's switching option.     

Group diversity and decision quality: Amplification and attenuation of the framing effect

Do groups make better judgments and decisions than individuals? We tested the hypothesis that the advantage of groups over individuals in decision-making depends on the group composition. Our study used susceptibility to the framing effect as a measure of decision quality. Individuals were assigned to one of two perspectives on a choice problem. The individuals were asked to indicate their individual preference between a risky option and a risk-free option. Next, they were asked to consider the same (or a related) choice problem as a group. Homogeneous groups were composed of similarly framed individuals, while the heterogeneous ones were composed of differently framed individuals. In comparison to individual preferences, the homogeneous groups’ preferences were polarized, and thus the framing effect was amplified; in contrast, the heterogeneous groups’ preferences converged, and thus the framing effect was reduced to zero. The findings are discussed with regard to group polarization, the effects of heterogeneity on group performance, and the Delphi forecasting method.     

我国农村留守儿童问题与对策研究

近年来,农村留守儿童问题成为一个越来越突出的社会问题。教育问题、心理问题和安全问题是当前农村留守儿童普遍面临的三大问题。农村留守儿童问题的妥善解决需要政府、学校、家庭和社会各方面共同的努力。     

Shadow costs of incomplete information and short sales in the valuation of the firm and its assets

This paper presents a simple framework for the valuation of compound options within shadow costs of incomplete information and short sales. The shadow cost includes two components. The first component is the product of pure information cost due to imperfect knowledge and heterogeneous expectations. The second component represents the additional cost caused by the short-selling constraint. Information costs are linked to Merton's (1987. Journal of Finance 42, 510) model of capital market equilibrium with incomplete information, CAPMI. This model is extended by Wu et al. (1996. Review of Quantitative Finance and Accounting, 7, 136) who propose an incomplete-information capital market equilibrium with heterogeneous expectations and short sale restrictions, GCAPM. This model is used in our paper to provide for the first time in the literature analytic solutions for derivatives in the presence of both shadow costs of incomplete information and short sales.When deriving the compound call option formula, we consider a call option on a stock, which is itself an option on the assets of the firm. Our methodology incorporates shadow costs of incomplete information and short sales on the firm's assets as well as the effects of leverage in the capital structure. The formula can be useful in the valuation of several corporate liabilities in the presence of information uncertainty and short sales constraints about the firm and its cash flows. Our analysis can be used for the valuation of several real options.     

实物期权方法在企业投资决策中的应用研究

为了更好的对投资项目进行评估,引入了实物期权理论,为项目投资决策提供全新的思路。本文介绍了实物期权理论,并根据企业投资决策的特点,介绍了实物期权的分类和特征,提出了实物期权应用于企业投资决策的一般步骤。     

Hierarchies and information-processing organizations

This paper analyzes organizational structures that minimize information processing costs for a specific organizational task. Organizations consist of agents of limited ability connected in a network. These agents collect and process information, and make decisions. Organizations implement strategies – mappings from environmental circumstances to decisions. The strategies are exogenously given from a class of “pie” problems to be defined in this paper. The notion of efficiency is lexicographic: the primary criterion is minimizing the number of agents, and the secondary criterion is minimizing the number of connections between the agents. In this modeling framework, efficient organizations are not hierarchical for a large number of problems. Hierarchies often fail to exploit fully the information processing capabilities of the agents because in a hierarchy, subordinates have a single superior. Received: 1 December 1995 / Accepted: 11 October 1998     

Towards right-shoring: a framework for off-and re-shoring decision making

Location decisions are crucial for manufacturing plants. While current research mainly stresses the cost considerations of location decisions, this research focusses on a more comprehensive decision-making process. Based on analyzing the motivations for off-and re-shoring, we present a decision-making framework which will help companies to ‘right-shore’. Through a multiple case study approach in the aeronautics industry, an industry known for its technical complexity and innovative nature, we will validate and broaden our initial decision-making framework based on literature. While analyzing this framework, it became apparent that the main motivation for offshoring in the aeronautic industry is far from being restricted to cost-cutting considerations. More specific, companies in this industry are willing to develop sustainable commercial partnerships in emerging countries to benefit from new capacities and resources. In the same vein, re-shoring decisions are grounded on long-term perspectives and are carefully balanced. While providing a comprehensive framework for offshoring and re-shoring decisions, our framework enables companies to make better informed decisions for choosing the right location for their plants.