Columbia Business School Research

Supply chain management is the most recently proposed set of tools to replace the total quality paradigm, which itself replaced innumerable previous sets of principles and managerial tools. The fundamentals are unchanged; the principles of managing for quality are quite robust and are easily adaptable to the task of supply chain management. The most obvious element that is new about supply chain management is the unprecedented sophistication of its information technology.

This paper describes novel market-based technologies that uniquely establish quantifiable and adjustable limits on the power of attackers, enable verifiable accountability for malicious attacks, and admit systematic and uniform monitoring and detection of attacks. These technologies, incorporated in the MarketNet system, establish a financial economy to regulate the trade and use of access rights in information systems. Resources are instrumented to use currency for access control and monitoring, establishing accountability in their use.

The authors present a new approach to culture and cognition, which focuses on the dynamics through which specific pieces of cultural knowledge (implicit theories) become operative in guiding the construction of meaning from a stimulus. Whether a construct comes to the fore in a perceiver's mind depends on the extent to which the construct is highly accessible (because of recent exposure).

This century has been marked by two great economic experiments. The outcome of the first set, the socialist experiment that began, in its more extreme form, in the Soviet Union in 1917, is now clear. The second experiment is the movement back from a socialist economy to a market economy. Ten years after the beginning of the transition in Eastern Europe and the Former Soviet Union: How do we assess what has happened? What are the lessons to be learned?

Unlike European-type derivative securities, there are no simple analytic valuation formulas for finite-lived American options, even when the underlying asset price has constant volatility. The early exercise feature considerably complicates the valuation of American contracts. The strategy taken in this paper is to rely on nonparametric statistical methods using market data to estimate the call prices and the exercise boundaries. A comparison is made with parametric constant volatility model-based prices and exercise boundaries.

Consider a queue with a stochastic fluid input process modeled as fractional Brownian motion (fBM).When the queue is stable, we prove that the maximum of the workload process observed over an interval of length t grows like y(log t)^1/(2-2H), where H > 1/2 is the self-similarity index (also known as the Hurst parameter) that characterizes the fBM and can be explicitly computed.

A model of molecular diversity is presented. The model, termed "Quantized Surface Complementarity Diversity" (QSCD), defines molecular diversity by measuring molecular complementarity to a fully enumerated set of theoretical target surfaces. Molecular diversity space is defined as the molecular complement to this set of enumerated surfaces. Using a set of known test compounds, the model is shown to be biologically relevant, consistently scoring known actives as similar.

We argue that a way culture influences decisions is through the reasons that individuals recruit when required to explain their choices. Specifically, we propose that cultures endow individuals with different rules or principles that provide guidance for making decisions, and a need to provide reasons activates such cultural knowledge. This proposition, representing a dynamic rather than dispositional view of cultural influence, is investigated in studies of consumer decisions that involve a trade-off between diverging attributes, such as low price and high quality.

We analyze a closely held corporation characterized by the absence of a resale market for its shares. We show that the founder of the firm can optimally choose an ownership structure with several large shareholders to force them to form coalitions to obtain control. By grouping member cash flows, a coalition internalizes to a larger extent the consequences of its actions and hence takes more efficient actions than would any of its individual members. The model has implications for the optimal bundling of cash flow and voting rights, and for the optimal number and size of shareholders.

We investigate how individuals learn from imagined might-have-been scenarios. We hypothesize that individuals are more likely to learn when they have responded to an event with upward-directed, self-focused counterfactual thoughts, and, additionally, that this learning process is inhibited by accountability to organizational superiors. Support for these hypotheses was obtained in two studies that assessed learning by aviation pilots from the experience of near accidents.

The research in this article examined the consequences of a failed attempt to reduce dissonance through a self-affirmation strategy. It was hypothesized that disconfirming participants' affirmations would reinstate psychological discomfort and dissonance motivation. In Experiment 1, high-dissonance participants who affirmed on a self-relevant value scale and received disconforming feedback about their affirmations expressed greater psychological discomfort (Elliot & Devine, 1994) than either affirmation-only participants or low-dissonance/affirmation disconformed participants.

Rapid comprehensive change in the physical pattern of a city is a minor revolution — as is the transformation of 42nd Street and Times Square. Two decades ago the agenda for change posed two big questions: Is it possible for cities to reshape what the market is likely to deliver in an area? Is large-scale redevelopment even a plausible political objective, especially when aggressive actions such as condemnation are deemed a necessary part of the strategy?

Sociologists contend that industries can be importantly characterized as sets of interlocking producer positions. This paper argues that this distinctively relational conception of a market represents a powerful framework for depicting and analyzing the process of technical change.

The present research is motivated by an interest in why organizational decision makers so often respond to accidents with remedy plans that focus narrowly on correcting human error rather than more environment-focused plans or more encompassing plans. We investigated the role of counterfactual thinking in the decision-making tendency toward human-focused plans. Our experiments indicated that even in a domain where human-focused remedies were not otherwise appealing, many participants decided on human-focused remedies after they had generated an “if only” conjecture about the accident.

We study the economic consequences of alternative hedge accounting rules in terms of managerial hedging decisions and wealth effects for shareholders. The rules we consider include the "fair-value" and "cash-flow" hedge accounting methods prescribed by the recent SFAS No. 133. We illustrate that the accounting method used influences the manager's hedge decision. We show that under no-hedge accounting, the hedge choice is different from the optimal economic hedge the firm would make under symmetric and public information.

Prior evaluations are frequently challenged and need to be revised. We propose that an important determinant of such revisions is the degree to which the challenge provides an opportunity to compare the target against a competitor. Whenever a challenge offers an opportunity, the information contained in the challene will carry a disproportionate weight in the revised judgments. We call this proposition the comparison-revision hypothesis.

Low inventory, a crucial part of just-in-time (JIT) manufacturing systems, enjoys increasing application worldwide, yet the behavioral effects of such systems remain largely unexplored. Operations research (OR) models of low-inventory systems typically use a simplifying assumption that processing times of individual workers are independent random variables. This leads to predictions that low-inventory systems will exhibit production interruptions leading to lower productivity. Yet empirical results suggest that low-inventory systems do not exhibit the predicted productivity losses.

Cultural commentators addressing the differences between high art and mere entertainment have suggested that the standards of popular appeal governing the tastes of ordinary consumers differ from the criteria for excellence employed by professional critics in rendering expert judgments. These concerns appear in discussions of the cultural hierarchy (distinguishing among levels of tastes) and in claims that commercialism tends to degrade cultural objects (by catering to tastes that represent the lowest common denominator).

Research extending over twenty years in behavioral decision theory has led to the development of two important research streams--mental accounting and reason-based choice. This paper explores recent research on the role of mental accounting and reason-based choice in the construction of consumer preferences. Evidence suggests that the principles of mental accounting often regulate the purchase and consumption of luxuries and that reasons may play an important part in this process.

Affective states of the same valence may have distinct, yet predictable, influences on decision processes. Results from three experiments show that, in gambling decisions, as well as in jobselection decisions, sad individuals are biased in favor of highrisk/high-reward options, whereas anxious individuals are biased in favor of low-risk/low-reward options. We argue that these biases occur because anxiety and sadness convey distinct types of information to the decision-maker and prime different goals.

Several experiments provided evidence that negotiators make systematic errors in personality-trait attributions for the bargaining behaviors of their counterparts. Although basic negotiation behavior is highly determined by bargaining positions, negotiators primarily interpret their counterpart's behavior in terms of the counterpart's personality, such as his or her level of cooperativeness or agreeableness.

Stochastic Economic Lot Scheduling Problems (ELSPs) involve settings where several items need to be produced in a common facility with limited capacity, under significant uncertainty regarding demands, unit production times, setup times, or combinations thereof. We consider systems where some products are made-to-stock while another product line is made-to-order. We present a rich and effective class of strategies for which a variety of cost and performance measures can be evaluated and optimized efficiently by analytical methods.

One possible explanation for bidding firms earning positive abnormal returns in diversifying acquisitions in the 1960s is that internal capital markets were expected to overcome the information deficiencies of the less-developed capital markets. Examining 392 bidder firms during the 1960s, we find the highest bidder returns when financially "unconstrained" buyers acquire "constrained" targets. This result holds while controlling for merger terms and for different proxies used to classify firms facing costly external financing.

We examine the ability of a dynamic asset-pricing model to explain the returns on G7-country stock market indices. We extend Campbell's (1996) asset-pricing model to investigate international equity returns. We also utilize and evaluate recent evidence on the predictability of stock returns. We find some evidence for the role of hedging demands in explaining stock returns and compare the predictions of the dynamic model to those from the static CAPM. Both models fail in their predictions of average returns on portfolios of high book-to-market stocks across countries.

This paper deals with Markov decision processes with a countable state space. We demonstrate that a single, relatively simple condition suffices to guarantee that the value-iteration method converges and that an optimal policy can be computed via this method, once the existence of a solution to the average cost optimality equation has been established via any of the many available sets of existence conditions.

We analyze a randomized version of the deterministic linear programming (DLP) method for computing network bid prices. The method consists of simulating a sequence of realizations of itinerary demand and solving deterministic linear programs to allocate capacity to itineraries for each realization. The dual prices from this sequence are then averaged to form a bid price approximation. This randomized linear programming (RLP) method is only slightly more complicated to implement than the DLP method.

This survey reviews the forty-year history of research on transportation revenue management (also known as yield management). We cover developments in forecasting, overbooking, seat inventory control, and pricing, as they relate to revenue management, and suggest future research directions. The survey includes a glossary of revenue management terminology and a bibliography of over 190 references.

It is argued that a more realistic picture of the true diversification benefits from emerging equity markets is available from 3 investment vehicles that provide access to emerging market returns, while circumventing many of the restrictions and costs that limit the conclusions of previous emerging market research.

This paper develops a variance reduction technique for Monte Carlo simulations of path-dependent options driven by high-dimensional Gaussian vectors. The method combines importance sampling based on a change of drift with stratified sampling along a small number of key dimensions. The change of drift is selected through a large deviations analysis and is shown to be optimal in an asymptotic sense. The drift selected has an interpretation as the path of the underlying state variables which maximizes the product of probability and payoff—the most important path.

Previous research has shown that wages in industries characterized by higher rates of technological change are higher. In addition, there is evidence that skill-biased technological change is responsible for the dramatic increase in the earnings of more educated workers relative to less educated workers that took place during the 1980s.

Marketers all over the world agree that the Internet will have a major impact on the way firms do business. What changes will exactly occur, however, is hard to predict as the Internet is in a phase of rapid growth and constant change. Patterns are difficult to isolate, especially since despite its explosive growth, today, the Net is still in its infancy, only being available to a small proportion of people. In spite of this general lack of reliable patterns, one consensus among managers seems to be that the Internet is likely to intensify price competition.