Investment decisions in the theory of finance: Some antinomies and inconsistencies

The net-present-value rule is a pillar of modern finance theory. As known, it is a capital budgeting rule. Finance theory prescribes the investor to compare the opportunity in hand with an asset of equivalent risk, i.e. to discount cash flows with a risk-adjusted rate of return. This paper aims at showing that inconsistencies and antinomies arise when applying the above-mentioned rule. Further, it turns out that it is actually impossible to compare alternatives equivalent in risk and any decision maker cannot prevent herself to violate the above tenet.     

Chance-constrained programming models for capital budgeting with NPV as fuzzy parameters

In an uncertain economic environment, experts’ knowledge about outlays and cash inflows of available projects consists of much vagueness instead of randomness. Investment outlays and annual net cash flows of a project are usually predicted by using experts’ knowledge. Fuzzy variables can overcome the difficulties in predicting these parameters. In this paper, capital budgeting problem with fuzzy investment outlays and fuzzy annual net cash flows is studied based on credibility measure. Net present value (NPV) method is employed, and two fuzzy chance-constrained programming models for capital budgeting problem are provided. A fuzzy simulation-based genetic algorithm is provided for solving the proposed model problems. Two numerical examples are also presented to illustrate the modelling idea and the effectiveness of the proposed algorithm.     

两货栈及延期支付和现金折扣情形下变质产品的最优订货策略

已有的两货栈库存模型通常不考虑将延期支付和现金折扣相结合的情形,但实际上,供应商在给予销售商延期支付政策的同时,也会实施现金折扣策略以激励销售商尽快付款,加快资金周转,减少坏账损失。为此,本文建立了延期支付和现金折扣情形下变质产品的两货栈库存模型,并对模型的最优解进行理论分析,给出了最优解的求解步骤。最后通过数值算例对模型的可行性进行了验证,并分析了模型参数变化对最优订货策略和最优付款时间的影响。     

两货栈及延期支付和现金折扣情形下变质产品的最优订货策略

已有的两货栈库存模型通常不考虑将延期支付和现金折扣相结合的情形,但实际上,供应商在给予销售商延期支付政策的同时,也会实施现金折扣策略以激励销售商尽快付款,加快资金周转,减少坏账损失。为此,本文建立了延期支付和现金折扣情形下变质产品的两货栈库存模型,并对模型的最优解进行理论分析,给出了最优解的求解步骤。最后通过数值算例对模型的可行性进行了验证,并分析了模型参数变化对最优订货策略和最优付款时间的影响。     

Optimizing venture capital investments in a jump diffusion model

We study two practical optimization problems in relation to venture capital investments and/or Research and Development (R&D) investments. In the first problem, given the amount of the initial investment and the cash flow structure at the initial public offering (IPO), the venture capitalist wants to maximize overall discounted cash flows after subtracting subsequent investments, which keep the invested company solvent. We describe this problem as a mixture of singular stochastic control and optimal stopping problems. The second problem is concerned with optimal dividend policy. Rather than selling the company at an IPO, the investor may want to harvest technological achievements in the form of dividend when it is appropriate. The optimal control policy in this problem is a mixture of singular and impulse controls. E. Bayraktar was supported in part by the National Science Foundation, under grant DMS-0604491.     

Term structure of discount rates for firms in the insurance industry

There is strong evidence in the literature for the hypothesis that interest rates and the market risk premium are not constant during the business cycle. The beta risk of firms in the insurance industry is also time-varying. The major implication of these results is that discount rates for risky cash flows are time varying and must obey a term structure similar to the term structure of interest rates. The purpose of this paper is to estimate discount rates for cash flows with different time horizons for the U.S. insurance industry and for different insurance sectors. We find that the term structure cost of capital takes on different shapes depending on the business cycle. It is therefore meaningful for insurers to evaluate risky projects by selecting a discount rate most appropriate for the nature and the time horizon of each project.     

模糊环境下资金预算的期望净现值模型

资金预算问题是指对一项投资机会是否应该付诸实施进行判断.净现值方法(NPV)一直是现代资本预算方法的传统核心内容.将传统的净现值方法扩展到模糊环境下,讨论了当现金流入和现金流出为模糊变量情况下,如何选择最优的项目.建立了模糊环境下的均值NPV模型,并设计了基于模糊模拟的遗传算法,给出了模型问题的一般解决方法.     

Design,planning, scheduling,and control problems of flexible manufacturing systems

The design and use of flexible manufacturing systems (FMSs) involve some intricate operations research problems.FMS design problems include, for example, determining the appropriate number of machine tools of each type, the capacity of the material handling system, and the size of buffers.FMS planning problems include the determination of which parts should be simultaneously machined, the optimal partition of machine tools into groups, allocations of pallets and fixtures to part types, and the assignment of operations and associated cutting tools among the limited-capacity tool magazines of the machine tools.FMS scheduling problems include determining the optimal input sequence of parts and an optimal sequence at each machine tool given the current part mix.FMS control problems are those concerned with, for example, monitoring the system to be sure that requirements and due dates are being met and that unreliability problems are taken care of. This paper defines and describes these FMS problems in detail for OR/MS researchers to work on.     

Volatility estimation for stochastic project value models

One of the key parameters in modeling capital budgeting decisions for investments with embedded options is the project volatility. Most often, however, there is no market or historical data available to provide an accurate estimate for this parameter. A common approach to estimating the project volatility in such instances is to use a Monte Carlo simulation where one or more sources of uncertainty are consolidated into a single stochastic process for the project cash flows, from which the volatility parameter can be determined. Nonetheless, the simulation estimation method originally suggested for this purpose systematically overstates the project volatility, which can result in incorrect option values and non-optimal investment decisions. Examples that illustrate this issue numerically have appeared in several recent papers, along with revised estimation methods that address this problem. In this article, we extend that work by showing analytically the source of the overestimation bias and the adjustment necessary to remove it. We then generalize this development for the cases of levered cash flows and non-constant volatility. In each case, we use an example problem to show how a revised estimation methodology can be applied.     

The optimal order and payment policies for deteriorating items in discount cash flows analysis under the alternatives of conditionally permissible delay in payments and cash discount

This study investigates a deteriorating inventory problem in which the supplier simultaneously offers the retailer either a conditionally permissible delay in payments or a cash discount. In the case of a conditionally permissible delay, if the retailer orders more than a predetermined quantity, then he/she has a grace period to make the full payment. Otherwise, he/she must pay the payment for goods of certain proportion first while receiving the goods and has a grace period to pay off the rest. As to a cash discount, if the retailer pays for the entire amount of the order within a certain short period, then he/she will receive a cash discount from the supplier. In additions, from a financial standpoint, all cash outflows related to the inventory control that occur at different points of time have different values. Hence, it is necessary to take account of the factor of time value of monetary when drafting the replenishment policy. In a word, this paper uses an alternate approach-discount cash flow (DCF) analysis to establish an inventory problem for deteriorating items in which the supplier provides the retailer either a conditionally permissible delay or a cash discount. We then study the necessary and sufficient conditions for finding the optimal solution. Furthermore, we establish several theoretical results to obtain the solution that provides the smallest present value of all future cash flows. Finally, several numerical examples are given to illustrate the results and obtain some managerial insights.     

基于营运资金信息匹配平台的供应链金融动态折扣决策研究

当前逐渐受到实业界关注的一种新型供应链金融模式是基于营运资金信息匹配平台的动态折扣。本文针对两级供应链的动态折扣决策问题进行建模,揭示了动态折扣的应用对于改善供应链参与方现金流的影响机理。首先通过考虑供需双方动态折扣的独立决策,得出日折扣率的边界条件、双方效用最大时的日折扣率、买方混合还款方式下营运资金的最优准备方案和最低边界值;其次考虑供需双方动态折扣的最优决策,推导出在不同折扣率和利率关系下的最优还款策略,研究表明动态折扣可以明显提升供需双方的利润情况。     

Economic Order Quantity and Quantity Discounts under Date-terms Supplier Credit: A Discounted Cash Flow Approach

This paper examines economic order quantity and optimal order quantity under both all-units and incremental-quantity discounts when purchase cost, order cost, and carrying cost are all incurred on date-terms supplier credit. Payment dates for the three cost components need not be the same. The traditionally-used periodic-cost minimization methodology which is insensitive to differences in the timing of various within-period cash flows is replaced with a discounted cash flow methodology. Differences in the characteristics of day-terms and date-terms solutions to the quantity discount case are high-lighted.     

稳健资产负债管理最优化模型及实证分析

本文提出一种新的稳健资产负债模型最优化模型.该模型考虑了利率的不确定性对未来现金流、资金成本和资产收益率的影响.我们通过构建情景树反映未来的利率变化的情景结构.由于最优决策对利率的预测十分敏感,我们提出系数预测值可在一定误差范围内的稳健资产负债最优化模型.实证分析结果表明,从收益与风险均衡的角度看,稳健优化模型产生的保守解优于系数确定的优化模型产生的最优解.     

Capital renewal as a real option

We consider the timing of replacement of obsolete subsystems within an extensive, complex infrastructure. Such replacement action, known as capital renewal, must balance uncertainty about future profitability against uncertainty about future renewal costs. Treating renewal investments as real options, we derive an optimal solution to the infinite horizon version of this problem and determine the total present value of an institution’s capital renewal options. We investigate the sensitivity of the infinite horizon solution to variations in key problem parameters and highlight the system scenarios in which timely renewal activity is most profitable. For finite horizon renewal planning, we show that our solution performs better than a policy of constant periodic renewals if more than two renewal cycles are completed.     

Sensitivity measures for equity investments

By differentiating a discounted cash flow valuation formula(expressed in real terms), with respect to the underlying fundamentalreal variables, we derive ‘sensitivity measures’for equity investments. These show how the present value ofexpected future dividends will vary as the real discount ratechanges and the long-term real dividend growth rate changes.In both cases, sensitivity depends on dividend yield: the lowerthe dividend yield, the more sensitive the stock to changesin both the real discount rate and the real growth rate. Wealso derive a total differential model which allows for simultaneouschanges in both the real discount rate and the real growth rate,and briefly compare this model with the model of Leibowitz etal. for equity duration.     

Insurance valuation: A computable multi-period cost-of-capital approach

We present an approach to market-consistent multi-period valuation of insurance liability cash flows based on a two-stage valuation procedure. First, a portfolio of traded financial instrument aimed at replicating the liability cash flow is fixed. Then the residual cash flow is managed by repeated one-period replication using only cash funds. The latter part takes capital requirements and costs into account, as well as limited liability and risk averseness of capital providers. The cost-of-capital margin is the value of the residual cash flow. We set up a general framework for the cost-of-capital margin and relate it to dynamic risk measurement. Moreover, we present explicit formulas and properties of the cost-of-capital margin under further assumptions on the model for the liability cash flow and on the conditional risk measures and utility functions. Finally, we highlight computational aspects of the cost-of-capital margin, and related quantities, in terms of an example from life insurance.     

Short-Term Capacity Adjustment with Offline Production for a Flexible Manufacturing System under Abnormal Disturbances

Large production variations caused by abnormal disturbances can significantly reduce the production capacity of a flexible manufacturing system (FMS). To prevent production delays, short-term capacity adjustment strategies can be used to augment the capacity of the FMS, such as working overtime, using alternative tools that are suited for faster processing, and producing parts outside of the FMS. We propose a mixed integer programming (MIP) model to obtain an optimal production plan for a multi-machine FMS. Our model evaluates both the FMS loading decision and the effective use of short-term capacity adjustment strategies to minimize the total part production cost. We develop an iterative procedure to solve the model that uses the Lagrangian relaxation method for finding lower bounds and a Lagrangian heuristic for obtaining feasible solutions. The procedure exploits certain special structures found in the Lagrangian multipliers which enable us to obtain good solutions to reasonably large test problems quickly.     

Production and payment policies for an imperfect manufacturing system with discount cash flows analysis in fuzzy random environments

ABSTRACT

This paper considers an imperfect manufacturing system with credit policies in fuzzy random environments. The supplier simultaneously offers the retailer either a permissible delay in payments or a cash discount and retailer in turn provides its customer a permissible delay period. We used an alternate approach – discount cash flow analysis to establish an inventory problem. It is assumed that the elapsed time until the machine shifts from ‘in-control’ state to ‘out-of-control’ state is characterized as a fuzzy random variable. As a function of this parameter, the profit function is also a random fuzzy variable. Based on the credibility measure of fuzzy event, the model with fuzzy random elapsed time can be transformed into a crisp model . We establish several theoretical results to obtain the solution that provides the largest present value of all future cash flows. Finally, numerical example is given to illustrate the results and obtain some managerial insights.     

Resource leasing and optimal periodic capital investments

In this paper we analyse a fishery resource exploitation model in which a single firm or a cartel has leased the rights to manage the resources independently. Two variables, resource level and the capital level, determine the dynamics of the resource system. The leasing contract includes an incentive for the agent to maintain the resource level high. The main result is that sole-agent resource management and efficiency of the resource use do not necessarily imply that the fishery is stabilized at a unique steady state level. Instead, the optimal resource exploitation may lead to periodic capital investments in fishing vessels and gear which in turn causes cycles in the resource economy. We show analytically that nonzero discount rate and low capital depreciation rate both favor the conditions under which periodic optimal solutions may occur. Simulation results related to a Baltic herring fishery are used to illustrate the results.This research was partly supported by the Austrian Science Foundation under contract number P7783. The support of the Academy of Finland and Yrjö Jahnsson Foundation to V. K. is greatly appreciated. We thank Carl Folke, Mikael Hildén and Steffen Jørgensen and three anonymous referees for helpful comments. V. K. thanks the Beijer Institute of the Royal Swedish Academy of Science for its hospitality.     

An Inventory Model for Deteriorating Items with?Two?Levels of Trade Credit Taking Account of Time Discounting

This paper presents an extended inventory model of Huang (J. Oper. Res. Soc. 54, 1011–1015, 2003), which investigated the retailer’s optimal inventory policy under two levels of trade credit. Herein, we consider the impact of a replenishment policy on the timing of the cash flows associated with payments to suppliers and revenue streams from customers. That is, the same cash amount will possess different money value at different future time. To see this, we adopt the more appropriate net present value (NPV) object instead of the average cost objective. In addition, the deteriorating effects will be incorporated in this inventory model, and the time to deterioration of each item follows an exponential distribution. The discounted cash flow (DCF) approach is used to derive the optimal solution in this study. Furthermore, we first show that the optimal solution not only exists bus also is unique. Then, we provide a theorem to locate the optimal ordering policy. Finally, a numerical example for illustration is provided.