Minimizing mean absolute deviation of completion time about a common due window subject to maximum tardiness for a single machine

This study deals with the problem of scheduling jobs on a single machine to minimize the mean absolute deviation of the job completion time about a large common due window subject to the maximum tardiness constraint. Using the well-known three-field notation, the problem is identified as MAD/large DueWindow/T_max. The common due window is set to be large enough to allow idle time prior to the beginning of a schedule to investigate the effect of the T_max constraint. Penalties arise if a job is completed outside the due window. A branch and bound algorithm and a heuristic are proposed. Many properties of the solutions and precedence relationships are identified. Our computational results reveal that the branch and bound algorithm is capable of solving problems of up to 50 jobs and the heuristic algorithm yields approximate solutions that are very close to the exact solution.     

Cobacabana (control of balance by card-based navigation): A card-based system for job shop control

Existing card-based production control systems such as Kanban are mostly dedicated to repetitive production environments. Cards-based systems for job shop control are lacking, while particularly this industry segment shows a need for simple control systems. This paper aims at filling the gap by presenting a simple card-based system for job shop control, the Cobacabana (control of balance by card-based navigation) system. It is based on the concept of workload control (WLC), which has already proven its value in job shops. Developments towards more robust norms now allow for transforming the WLC concept into a simple card-based system, with loops of cards accompanying orders from release until completion at critical work centers. Cards returning from work centers authorize the planner to release new orders. A card-based display supports the planner with an overview of the shop floor situation, based on non-released cards. An additional loop of cards between sales and planning enables support of the order acceptance and due date promising function. A card-based acceptance display indicates what delivery dates are realistic, considering the current workload situation. Both the scientific roots of the system and practical implementation issues are discussed in this paper.     

PRINCIPLES OF- ENGINEERING ECONOMIC ANALYSIS by John A. White,Marvin H. Agee and Kenneth E. Case,John Wiley & Sons,Inc., New York, 1984, 2nd Ed., xii + 546 pp., List $32.95.

In his three recent papers [3], [4], and [5], R.G. Beaves develops an Overall Rate of Return (ORR) project evaluation criterion based on the concept of the so-called transition point (TP) which he has defined in two different versions.¹ In the present contribution, it is shown that some projects may produce undefined ORRs for either TP version, and that other ORR-like criteria [7] may also generate undefined results for projects for which the Net Present Value (NPV) criterion is defined. To eliminate the cases of the ORR undefinability, a generalization of the ORR criterion is proposed that makes this criterion fully NPV compatible and applicable to both investment and financing projects. This criterion embraces all the existing ORR approaches that are based on the notions of the initial and terminal wealths, including both of Beaves' approaches.     

A Review of“BUSINESS INVESTMENT POLICY”* A Critical Review GEORGE TERBORGH: Machinery and Allied Products Institute and Council for Technological Advancement, 1200 Eighteenth Street,N.W., Washington,D.C., 1958. 260 pp. $6 (A MAPI Study and Manual)

In my previous article on “Project Justification in a Multi-product Chemical Plant”, which appeared in the Fall 1959 issue of The Engineering Economist, I discussed the underlying causes for equipment acquisition and replacement in the chemical industry, and followed with a presentation of the payout-time technique for evaluating capital expenditure, as designed by a leading dye and pharmaceutical plant. Many other well-known techniques, such as the Annual Cost method, the Discounted Cash Flow, and the MAPI approach, are also available to management. However, none of the techniques mentioned relieves management of the basic responsibility for making the ultimate decisions regarding capital acquisition for expansion or replacement. The methods do present management with an analysis pointing up the relative merits of a given type of investment, and give some indication as to which alternative is the more desirable. Management, nevertheless, must assume responsibility for the final decision.     

More theory,in theory

An important aspect of the milk and dairy industry in the European Community is the reaction of milk producers to milk prices. In theory farmers behave like the economic man of basic economic textbooks. In practice, farmers behave quite differently, ie they increase their production when prices fall. For policy makers in the field of dairy products it is essential to know the reaction of the farming industry. Surprisingly this information is not available in the EEC; there are various opinions and estimates but they are heavily disputed. However, we now have the results of a study which can settle the dispute.¹ It is interesting to see the results and to notice that there really is a fundamental problem involved, ie how to discriminate between economic models.     

Private production and Chinese communes

The article by Ansell, Hay and Griffin, ¹ suggests a number of interesting, if guarded, conclusions about the impact of private production on the equality of income between teams and between households in Chinese communes. In general, the authors argue that an increase in the amount of income generated from private rather than collective sources may well be having an equalizing effect at both levels. As they rightly point out, developments in China of this nature are of great interest to all those concerned with alternative development strategies, given the stated aim of previous Chinese policies to produce growth with a high degree of equity. The major changes in Chinese rural policy in recent years have led to considerable re-evaluation of past performance, both within China and among outside observers. Furthermore, it is by no means clear that a stable set of policies is yet in place. In particular the introduction of the many types of production responsibility systems is having a major impact on almostall aspects of Chinese agriculture. Within this context, it becomes all the more critical to ensure that hypotheses and conclusions drawn from recent developments are soundly based and take account of the comprehensive restructuring which is underway.     

A review of: “CAPITAL BUDGETING: PLANNING AND CONTROL OF CAPITAL EXPENDITURES” by John J. Clark,Thomas J. Hindenlang,and Robert E. Pritchard,Prentice-Hall,Englewook Cliffs,New Jersey, 1979, ix + 468 pages, $22.00 list.

If one wants to Identify the IRR's of a project, it is always helpful to know the interval within which they occur. In his recent paper de Faro presented two approaches to the determination of an upper bound to the IRR's. In the present contribution it is shown how an approach providing an upper bound can readily be applied to establish a corresponding lower bound, and vice versa. Also four powerful new approaches to the formulation of the bounds to a project's IRR's are introduced and evaluated, as well as some interesting “by-products” of the main-stream considerations are discussed. Finally, it is shown that the presented approaches can easily be applied to the determination of bounds for the real zeros of a polynomial.     

Incentive policy in Chinese collective agriculture — a comment

In the May issue of FOOD POLICY, Gek-boo Ng presented an interesting analysis of incentive policies in the Chinese system of collective agriculture,¹ in order to assess their impact on agricultural development in the People's Republic of China. The topic is of extreme importance to other developing countries seeking to emulate China's success in eliminating rural poverty. Ng's paper is well documented and highly informative. However, due to the fragmentary nature of the available data, and to limitations in Ng's analytical framework, the analysis seems to provide only limited support for his general conclusion that the incentive policies he examines have played an important role in China's agricultural development. The conclusion may eventually be warranted, but at present it seems somewhat premature.     

An integrated product planning model for pricing and bundle selection using Markov decision processes and data envelope analysis

When bundling products during the product planning stage, there are a number of possible combinations that can be offered to customers. Consider a firm that offers N distinctive products, then there are 2^N−(N+1) possible bundling combinations. Now, if we wish to make pricing and bundle selection decisions, keeping in my mind limited inventory and a finite time horizon, then the size of the state space could be very large and finding an optimal solution could be impossible. To tackle this issue, we formulate an integrated model that utilizes a Markov decision process and data envelope analysis. Bundle selections are made using data envelope analysis in each decision epoch. Once the efficient bundles are selected they are priced by solving a Markov decision process using dynamic programming. Numerical examples are solved to exhibit the model's potential in solving real-world problems.     

A Three-phase Approach to an Enhanced Index-tracking Problem with Real-life Constraints

Abstract

Enhanced index tracking is an emerging strategy for investing money in the stock market and is aimed at achieving outperformance over a given benchmark index while achieving a low tracking error. We consider the problem of rebalancing a portfolio for an enhanced index tracking strategy subject to various real-life constraints, including a lower bound and an upper bound on the expected tracking error. To solve this problem, we propose a three-phase approach consisting of preprocessing, optimization, and learning. In a computational experiment, we applied this approach to rebalance a given portfolio on a monthly basis over a time horizon of 10 years; the data for the S&P 500 benchmark index were provided by the investment company Principal Global Investors. Our approach generated portfolios that were provably close to optimality for all monthly rebalancing decisions. Over the entire horizon of 10 years, the portfolios devised by our approach yielded cumulative returns higher than the S&P 500 index after transaction costs with a moderate tracking error.     

Lower Bound Estimation – Quantile Regression and Simplex Method: An Application to Italian Manufacturing Sectors

This paper estimates Sutton's lower bound [1991, 1998] by quantile regression, and thus shows the influence of outliers on previous estimates that used the simplex method. The lower bound estimates are obtained separately for exogenous and endogenous sunk cost industries in Italian manufacturing sectors in 1995, using microdata from the SCI'95 (Firms Accounts System) survey conducted by ISTAT (National Institute of Statistics, Italy). The results suggest that Sutton's predictions are robust.     

Cereal shortages and adjustment in the Sahel

In spite of insufficient agricultural and demographic statistics for this region of Africa, several estimates of cereal production per head suggest that the average harvest in these arid zones provides slightly less than the quantity needed for domestic consumption. Alarmed by the drought of 1968–1973 and the resulting famine of 1973,¹ the development agencies questioned the capacity of the Sahel countries to feed their populations. ‘Is self-sufficiency in food a realistic objective?’, asked Robert Hirsch at the Noakchott Colloquium.² Statistical analysis leads to the conclusion that improvement is technically possible, and that the eight countries of CILSS, as a whole, should be able to achieve self-sufficiency in millet, sorghum and maize. However, certain individual countries will not be able to meet domestic needs. Moreover, Hirsch states that urban demand is increasing for corn and rice, which are difficult to produce locally and costly to import. (CILSS is the Comité Inter-états de Lutte contre la Sécheresse au Sahel).     

Impact of the alternate wetting and drying (AWD) water-saving irrigation technique: Evidence from rice producers in the Philippines

This article evaluates the impacts of a controlled irrigation technique in rice production called alternate wetting and drying (AWD). Propensity score matching (PSM) and regression-based approaches applied to farm-level survey data are used to achieve the objective of the study. The PSM and regression-based approach accounts for the potential bias due to selection problems from observable variables. Results of the impact analysis using both empirical approaches indicate that AWD, particularly the “Safe AWD” variant, reduces the hours of irrigation use (by about 38%), without a statistically significant reduction in yields and profits. This reduction in irrigation time translates to corresponding savings in the amount of irrigation water and pumping energy used. However, further analysis of the impact estimates suggests that the potential magnitude of the selection bias based on unobservable variables may still be able to eliminate the measured impact from the PSM and regression-based techniques that only control for selection based on observable variables. Hence, the current impact results have to be interpreted with caution and further data collection is needed to construct a panel data that would allow one to account for selection problems due to unobservable variables and, consequently, better estimate the AWD impact.     

SAM — a baby with many faces

In the last issue of Food Policy, two articles appeared on the subject of the Mexican Food System, or the Sistema Alimenticio Mexicano (SAM). The first article by Frank Meissner¹ reviewed the background to SAM, the proposed strategies, intended targets, its funding and put forward a strong case for considering SAM as a constructive policy for alleviating Mexico's food and nutrition problems. However, Michael Redclift commented in his article that:² ‘There are three principal points to be made of Dr Meissner's article: its interpretation of Mexico's recent agrarian development is questionable; it does not distinguish between the analysis provided in the SAM documents and the policy measures to which they give rise; and, it glosses over serious problems of implementation, giving too little weight to the participatory element without which SAM is doomed to failure’. This rejoinder is Frank Meissner's response to Michael Redclift's comments.     

Some predictors of SMJ article impact

Article impact is becoming an increasingly popular metric for assessing a scholar's influence, yet little is known about its properties or the factors that affect it. This study tests whether author, article, and methodological attributes influence the impact of SMJ articles, defined as summed counts of article citations. Findings reveal that authors having fewer, more‐often cited articles tended to have SMJ articles that received the most citations. In addition, whether an article appears in a regular or a special issue is not a stable predictor of its impact. Moreover, empirical articles that test primary data, control for more threats to internal validity, and have higher statistical power tend to receive more citations. Further, an article's long‐term impact oftentimes becomes apparent shortly after its publication. Overall, the findings provide new insights into the determinants of impact and its temporal qualities and help explain some of the differences between high and average impact articles. The findings also underscore the need for transparency between author publication strategies (article volume, impact) and the requirements of his/her institution. Implications for authors, reviewers, editors, and administrative evaluation are offered. Copyright © 2005 John Wiley & Sons, Ltd.     

Specification and Testing the Profit-Concentration Relationship in Australian Manufacturing

Research in the mainstream of industrial organization has tested the relationship between profit rates (an index of performance) and concentration (an index of structure) including other variables (e.g., capital intensity, advertising intensity, growth, measures for barriers to entry, import and export intensity). Specification of this relationship is often largely ad hoc and its testing is subject to a number of statistical criticisms. Major criticisms that require attention are: i) omission of the relevant explanatory variables, ii) simultaneous causality among variables, and iii) measurement error in the variables. This paper derives a profit-concentration relationship from a well known oligopoly model. Empirical analysis is carried out against a sample of Australian manufacturing industries for 1984–85. The resulting estimates suggest the importance of dealing with each of the specification and testing issues in explaining the profit-concentration relationship.     

Reaffirming the CEO effect is significant and much larger than chance: A comment on Fitza (2014)

A recent study by Fitza argued that the prior estimates of the Chief Executive Officer (CEO) effect are conflated with events outside the CEO's control, are largely the result of random chance, and that the true CEO effect is smaller than has been previously estimated. We suggest that the empirical methodology employed by Fitza to support these claims substantially overstates the “random chance” element of the CEO effect. We replicate Fitza's findings, highlight methodological issues, offer alternative conclusions, and using multilevel modeling (MLM), suggest that his analyses mischaracterize the CEO effect. Copyright © 2016 John Wiley & Sons, Ltd.     

On the role of empirical industrial organization in competition policy

In this paper I consider the role of empirical industrial organization (IO) in competition policy. In particular, I consider the effect of the institutional setting in which competition policy is developed on the diffusion of ideas and techniques emerging from the empirical IO literature. In doing so my aims are two fold. First, I aim to understand the areas of competition policy most likely to provide fertile ground for future work, and those which are less likely to have an impact. And second, I hope to make a small step towards ensuring that the important potential synergies between competition policy and empirical IO are more fully developed — to the benefit of both communities and, more importantly, the public. This paper necessarily draws heavily on my experience in the UK, but many remarks may resonate more generally.     

A Review of: “THE STAGES OF ECONOMIC GROWTH” A Non-Communist Manifesto By W. W. Rostow Cambridge University Press,New York, 1960 179 pp. Cloth ed. $3.75; paper ed. $1.45

History records that political economy received at least perfunctory attention in what were then engineering schools, over one hundred and thirty years ago. In 1827, Valentine B. Horton, who was later to become a Whig congressman and to make and lose a fortune, became “a professor of Moral Philosophy and Political Economy” at the American Literary, Scientific and Military Academy, the forerunner of Norwich University.¹ During the 1840s and ′50s, many engineering schools included a few lectures in moral philosophy and political economy in their programs. More formal and more enthusiastic promotion of economics on engineering campuses was evident under the aegis of Francis Amasa Walker, a noted economist and statistician, who, after service at the Sheffield School at Yale, became president of Massachusetts Institute of Technology in the early l88Os. Under his guidance, and that of Davis R. Dewey, who became an assistant professor of Economics and Statistics at M.I.T. in 1888, economics began to flourish on at least one engineering campus.     

Competitive dynamics research: An insider’s odyssey

This paper introduces competitive dynamics research, a body of work that has emerged in the strategic management field over the last two decades. I will focus on my scholarly pursuit—both the substance and the process—during the early years of my faculty career. I will use my twelve core publications written during this period to outline the entire research program, highlight the makeup of each of the four sub-streams of the program, and show how these streams are linked. I will also share my personal learning in the process of building this research program. The paper aims to convey some firsthand experience for researchers and scholars, especially those starting in their careers and international scholars who are interested in publishing in major U.S.-based journals, so they can construct their own research programs and cope with the manifold process challenges in research and publishing.