Management Sciences and Quantitative Methods Commons^™

A Bayesian Inventory Model Using Real-Time Condition Monitoring Information, Rong Li, Jennifer Ryan

Research Collection Lee Kong Chian School Of Business

No abstract provided.

Deterministic Chaos In A Model Of Discrete Manufacturing, John J. Iii Bartholdi, Donald D. Eisenstein, Yun Fong Lim

Research Collection Lee Kong Chian School Of Business

A natural extension of the bucket brigade model of manufacturing is capable of chaotic behavior in which the product intercompletion times are, in effect, random, even though the model is completely deterministic. This is, we believe, the first proven instance of chaos in discrete manufacturing. Chaotic behavior represents a new challenge to the traditional tools of engineering management to reduce variability in production lines. Fortunately, if configured correctly, a bucket brigade assembly line can avoid such pathologies.

The Application Of Single-Pass Heuristics For U-Lines, Jaydeep Balakrishnan, Chun Hung Cheng, Kin Chuen Ho, Kum Khiong Yang

Research Collection Lee Kong Chian School Of Business

U-lines have been adopted in many manufacturing settings as part of JIT implementation. In this paper, we examine the applicability of existing straight-line heuristics for obtaining a balance on a U-line. We modify 13 single-pass heuristics and study the effectiveness of various heuristics under different problem conditions. An extensive computational study is carried out to help identify the best heuristics. In addition, we compare recent U-line procedures with a single-pass heuristic using some literature problems. Based on a single-pass heuristic, we compare the configurations of a straight- and U-line. © 2009 The Society of Manufacturing Engineers.

Maximizing Throughput Of Bucket Brigades On Discrete Work Stations, Yun Fong Lim, Kum Khiong Yang

Research Collection Lee Kong Chian School Of Business

One way to coordinate workers along an assembly line that has fewer workers than work stations is to form a bucket brigade. The throughput of a bucket brigade on discrete work stations may be compromised due to blocking even if workers are sequenced from slowest to fastest. For a given work distribution on the stations we find policies that maximize the throughput of the line. When workers have very different production rates, fully cross-training the workers and sequencing them from slowest to fastest is almost always the best policy. This policy outperforms other policies for most work distributions except for …

Marketing Strategy And Wall Street: Nailing Down Marketing's Impact, Dominique M. Hanssens, Roland T. Rust, Rajendra Kumar Srivastava

Research Collection Lee Kong Chian School Of Business

Stock prices are based in large part on corporate financial statements, augmented by analysis by stock analysts. The ultimate goal of any marketing expenditure should be to increase the value of the firm, but the road from marketing expenditure to stock price is usually circuitous. This is because marketing’s path to financial impact is through revenues, and the road to revenues runs through the customer.

A New Approach To The Measurement Of Polarization For Grouped Data, Eckart Bomsdorf, Clemens A. Otto

Research Collection Lee Kong Chian School Of Business

In this paper we develop a measure of polarization for discrete distributions of non-negative grouped data. The measure takes into account the relative sizes and homogeneities of individual groups as well as the heterogeneities between all pairs of groups. It is based on the assumption that the total polarization within the distribution can be understood as a function of the polarizations between all pairs of groups. The measure allows information on existing groups within a population to be used directly to determine the degree of polarization. Thus the impact of various classifi- cations on the degree of polarization can be …

Management And Self-Activity: Accounting For The Crisis In Profit-Taking, Stefano Harney

Research Collection Lee Kong Chian School Of Business

The crisis in measurement identified by those working in the tradition of Italian autonomia has consequences for the critique of accounting and management. If both capitalist work and the commodity are today communicative and overtly political, a critique that merely points to these characteristics will have no transformative effect. This paper uses the Trinidadian Marxist theorist C.L.R. James’s notion of self-activity to suggest that the crisis in measurement is a symptom of the separation of work and value. The institution of forms of self-management and what might be called wars of command begin to replace the governmentality of the wage …

Perceptions Of Corporate Social Responsibility: An Empirical Study In Singapore; Strategic Management Policy, Gilbert Yip Wei Tan, Rajah Vellan Komaran

Research Collection Lee Kong Chian School Of Business

In Singapore, there is no doubt that there have been efforts by various local and foreign corporations to incorporate some CSR principles in their operations. Indeed, there was a national initiative modeled after the tripartite approach to industrial relations where national economic and industrial issues are collectively resolved by the government, employers and employees. Against the backdrop of this national initiative and the effort by some corporations to incorporate CSR principles, not much is really known about the state of affairs in Singapore.

Residual Life Distributions From Component Degradation Signals: A Bayesian Approach, Nagi Gebraeel, Mark Lawley, Rong Li, Jennifer Ryan

Research Collection Lee Kong Chian School Of Business

No abstract provided.

Chaos-Induced Escape Over A Potential Barrier, L. Y. Chew, Hian Ann, Christopher Ting, C. H. Lai

Research Collection Lee Kong Chian School Of Business

We investigate the statistical parity of a class of chaos-generated noises on the escape of strongly damped particles out of a potential well. We show that statistical asymmetry in the chaotic fluctuations can lead to a skewed Maxwell–Boltzmann distribution in the well. Depending on the direction of skew, the Kramers escape rate is enhanced or suppressed accordingly. Based on the Perron–Frobenious equation, we determine an analytical expression for the escape rate’s prefactor that accounts for this effect. Furthermore, our perturbative analysis proves that in the zeroth-order limit, the rate of particle escape converges to the Kramers rate.

Solving Hierarchical Constraints Over Finite Domains With Local Search, Martin Henz, Roland H.C. Yap, Yun Fong Lim, Seet Chong Lua, J. Paul Walser, Xiao Ping Shi

Research Collection Lee Kong Chian School Of Business

Many real world problems have requirements and constraints which conflict with each other. One approach for dealing with such over-constrained problems is with constraint hierarchies. In the constraint hierarchy framework, constraints are classified into ranks, and appropriate solutions are selected using a comparator which takes into account the constraints and their ranks. In this paper, we present a local search solution to solving hierarchical constraint problems over finite domains (HCPs). This is an extension of local search for over-constrained integer programs WSAT(OIP) to constraint hierarchies and general finite domain constraints.The motivation for this work arose from solving large airport gate …

On Uncertainty, Ambiguity, And Complexity In Project Management, Michael T. Pich, Christoph H. Loch, Arnoud De Meyer

Research Collection Lee Kong Chian School Of Business

This article develops a model of a project as a payoff function that depends on the state of the world and the choice of a sequence of actions. A causal mapping, which may be incompletely known by the project team, represents the impact of possible actions on the states of the world. An underlying probability space represents available information about the state of the world. Interactions among actions and states of the world determine the complexity of the payoff function. Activities are endogenous, in that they are the result of a policy that maximizes the expected project payoff.

A key …

Microscopic Chaos And Gaussian Diffusion Processes, L. Y. Chew, Christopher Ting

Research Collection Lee Kong Chian School Of Business

In this paper, we construct and analyze a prototypical model of microscopic chaos. In particular, we extend the results of Beck and Shimizu to the case where the microscopic time scale r is no longer small. The upshot is that a non-Ornstein-Uhlenbeck deterministic process can generate a Gaussian diffusion process.

Scale-Invariant Behavior In A Spatial Game Of Prisoners’ Dilemma, Yun Fong Lim, Kan Chen, Ciriyam Jayaprakash

Research Collection Lee Kong Chian School Of Business

A spatially extended version of the game of prisoner’s dilemma, originally proposed by Nowak and May, is modified to include stochastic updating and found to exhibit scale-invariant behavior. Two critical regimes with different scaling behaviors are found; the corresponding exponents have been determined numerically. Spatially, the critical states are characterized by the existence of delicately balanced networks of defectors separating domains of cooperators; temporally, the evolution of the critical states following local perturbations is characterized by avalanches of various magnitudes, which cause restructuring of the networks of defectors on all scales.

Dynamics Of Dry Friction: A Numerical Investigation, Yun Fong Lim, Kan Chen

Research Collection Lee Kong Chian School Of Business

We perform extended numerical simulation of the dynamics of dry friction, based on a model derived from the phenomenological description proposed by Baumberger et al. [Nature (London) 367, 544 (1994)] and Heslot et al. [Phys. Rev. E 49, 4973 (1994)]. Under a quasistationary approximation, the model is related to the Dieterich-Ruina aging (or slowness) law, which was introduced by Dieterich [Pure Appl. Geophys. 116, 790 (1978); J. Geophys. Res. 84, 2161 (1979); in Mechanical Behavior of Crustal Rocks, edited by N. L. Carter et al., Geophysics Monograph No. 24 (AGU, Washington, DC, 1981), p. 103] and Ruina [J. Geophys. Res. …

A Bayesian Technique For Refining The Uncertainty In Global Energy Model Forecasts, F. Ted Tschang, Hadi Dowlatabadi

Research Collection Lee Kong Chian School Of Business

Global energy models have a large degree of uncertainty associated with them. This consists of uncertainty in the model structure as well as uncertainty in the exogenous input parameters. This paper combines Monte Carlo methods with Bayesian updating techniques to provide a method for refining the uncertainty in the Edmonds-Reilly global energy model. The Bayesian updating technique uses likelihood-based windows constructed from actual observations of the output variables to filter out the model simulations that do not conform with the observed output. The windows are based on outputs of energy consumption and carbon emissions. Two alternative model structures are examined: …

Event-Study Methodology Under Conditions Of Event-Induced Variance, Ekkehart Boehmer, Jim Masumeci, Annette B. Poulsen

Research Collection Lee Kong Chian School Of Business

Many authors have identified the hazards of ignoring event-induced variance in event studies. To determine the practical extent of the problem, we simulate an event with stochastic effects. We find that when an event causes even minor increases in variance, the most commonly-used methods reject the null hypothesis of zero average abnormal return too frequently when it is true, although they are reasonably powerful when it is false. We demonstrate that a simple adjustment to the cross-sectional techniques produces appropriate rejection rates when the null is true and equally powerful tests when it is false.

A Direct Test Of Rock's Model Of The Pricing Of Unseasoned Issues, Francis Koh, Terry Walter

Research Collection Lee Kong Chian School Of Business

Unique data availability and institutional arrangements for new issues in Singapore allow a direct test of the empirical implications of Rock's model of pricing unseasoned new issues. Our empirical results are consistent with the model. Specifically we find that the unseasoned new issues' anomaly disappears when the rationing associated with new issues is incorporated into the analysis. The winner's curse is evident in allocation patterns used in Singapore.