Price Manipulation and Quasi‐Arbitrage

In an environment where trading volume affects security prices and where prices are uncertain when trades are submitted, quasi‐arbitrage is the availability of a series of trades that generate infinite expected profits with an infinite Sharpe ratio. We show that when the price impact of trades is permanent and time‐independent, only linear price‐impact functions rule out quasi‐arbitrage and thus support viable market prices. When trades have also a temporary price impact, only the permanent price impact must be linear while the temporary one can be of a more general form. We also extend the analysis to a time‐dependent framework.     

The Organization of Supplier Networks: Effects of Delegation and Intermediation

In a one‐principal two‐agent model with adverse selection and collusion among agents, we show that delegating to one agent the right to subcontract with the other agent always earns lower profit for the principal compared with centralized contracting. Delegation to an intermediary is also not in the principal's interest if the agents supply substitutes. It can be beneficial if the agents produce complements and the intermediary is well informed.     

Asymptotic Distributions of Quasi‐Maximum Likelihood Estimators for Spatial Autoregressive Models

This paper investigates asymptotic properties of the maximum likelihood estimator and the quasi‐maximum likelihood estimator for the spatial autoregressive model. The rates of convergence of those estimators may depend on some general features of the spatial weights matrix of the model. It is important to make the distinction with different spatial scenarios. Under the scenario that each unit will be influenced by only a few neighboring units, the estimators may have ‐rate of convergence and be asymptotically normal. When each unit can be influenced by many neighbors, irregularity of the information matrix may occur and various components of the estimators may have different rates of convergence.     

知识型员工职业召唤、职业承诺与工作态度关系研究

对中国情景下知识型员工的职业召唤对组织承诺、工作满意度、离职意愿等工作态度的影响以及职业承诺在职业召唤与上述工作态度的中介作用进行实证检验。基于自我决定理论和已有关于召唤的相关研究结论,提出职业召唤-职业承诺-工作态度的关系假设模型,并以981位国有、民营及外(合)资企业的知识型员工作为研究对象,通过结构方程建模进行实证检验。研究结果表明,中国情景下知识型员工的职业召唤对组织承诺、工作满意度和离职意愿均有显著正向影响,职业承诺完全中介职业召唤与工作满意度和离职意愿的关系,部分中介职业召唤与组织承诺的关系。在中国情景下验证西方关于职业召唤的研究结论,结果表明职业召唤的培养对企业知识型员工的职业承诺、组织承诺和工作满意度均具有十分重要的作用,为职业召唤理论在中国情景下的验证和完善以及知识型员工的管理理论和企业实践提供新的视角。     

Cross‐training Decisions in Field Services with Three Job Types and Server–Job Mismatch*

To be cost‐effective, field service managers must balance the high cost of machine downtime with the high cost of cross‐training technicians in multiple skills. We study a field service system with three job types requiring three different skills. Each server has a primary skill, the cost of which is considered sunk, and up to two secondary skills, which is a managerial decision. We model two important characteristics that distinguish field services: server–job mismatch and the ratio of travel time to service time. We use a queueing framework and simulation to study three cross‐training decisions: the number of servers cross‐trained in secondary skills, the number of secondary skills each server should have, and the efficiency in each secondary skill. We find that complete cross‐training is cost‐effective in some field service situations. Typically, efficiency in secondary skills must be close to 100%, but when the probability of mismatch is high and the ratio of travel time to service time is high, efficiency in secondary skills must be less than 100%.     

Using the End‐User Computing Satisfaction (EUCS) Instrument to Measure Satisfaction with a Web Site

The purpose of this study is to revise and revalidate the End‐User Computing Satisfaction (EUCS) instrument to measure satisfaction with a Web site from a usability perspective. This study is especially important given the increased significance of the Web and the uniqueness of the Web as a computing environment. A total of 176 students participated in a lab simulation that involved a usability evaluation of the Lands' End Web site ( http://www.landsend.com ). Students were asked to complete a set of tasks, record their answers, and then complete the EUCS instrument. Confirmatory factor analysis and invariance analyses were conducted to test the reliability, validity, and generalizability of the revised EUCS. The results show that the EUCS is a valid and robust instrument in the Web environment but that one of the subfactors, timeliness, will need further refinement in the future. Usability practitioners can use the EUCS to measure end‐user satisfaction with a Web site and use the feedback for improving Web‐site design. We describe a case study of an actual usability application that utilized the revised EUCS effectively to support the design of building supply Web sites involving two types of end users, homeowners and contractors. We also propose a typology that researchers can use as a starting point to judge when it is necessary to revalidate an instrument like the EUCS. Finally, we discuss the limitations of our study and present avenues for future research.     

Career Commitment as a Complex Moderator of Organizational Commitment and Turnover Intention

This study investigated the moderating role ofcareer commitment on the relationships betweenemployees' perception of company practices andorganizational commitment, and between organizationalcommitment and turnover intention. Using a sample of 225researchers from eight business-related researchinstitutes in Korea, it was found that (1) careercommitment was perceived as distinct from the twodimensions of organizational commitment (affective andcontinuance) by Korean researchers; (2) careercommitment moderated the effect of employees' perceptionof supervisory support on affective commitment; and (3) career commitment also moderated the effect ofaffective commitment on turnover intention. Thepractical and conceptual implications of these resultsare discussed.     

Kernberg Versus Kohut: A (Case) Study in Contrasts

In this paper, the main concepts of Otto Kernberg and Heinz Kohut—two theorists who have greatly influenced clinical social work practice with severely disturbed patients—are presented, and then compared by using a case from the practice of the author. The case illustrates the value of utilizing some of the treatment principles put forward by Kernberg and Kohut without becoming too wedded to either of the overall treatment approaches they have formulated. Some aspects of the manner in which the practitioner determines when the treatment approach needs to be modified—to avoid the pitfalls of either being too wedded to an approach or too eclectic—are discussed as well.     

The Relationship Between Weight and Career Payoffs Among Women

The thesis that weight affects women's life chances for reaching high-status, white-collar jobs is tested with survey data gathered from a large aerospace organization (N = 306). It is hypothesized that women who are at or below their desirable weight will have higher incomes and occupational positions than women who are overweight, with human capital variables controlled. It is further hypothesized that weight will be most related to occupational position in male-dominated occupations and in occupations that involve frequent contact outside the firm. Results show that weight is related to income, but only at entry-level professional/managerial occupations. Weight is significantly related to occupational position, especially so in male-dominated occupations. Weight is not more strongly related to occupational position in jobs involving outside contact. Findings are consistent with the interpretation that discrimination based on weight in the general society extends to the inner workings of workplace organizations.     

Evaluation of Embedded Intelligent Real‐time Systems*

Over the past two decades, questions have surfaced about the effectiveness and contribution of intelligent systems to decision makers in a variety of settings. This paper focuses on the evaluation challenges associated with intelligent real‐time software systems that are embedded in larger host systems. With the proliferation of such systems in operational settings such as aerospace, medical, manufacturing, and transportation systems, increased attention to evaluations of such systems, and to resulting software safety, is warranted. This paper describes one such evaluation and proposes a set of evaluation criteria for embedded intelligent real‐time systems (EIRTS). Implications of the evaluation and the evaluation criteria are discussed.