A Note On Long Memory Time Series

This note presents the fractional integrated processes which are the main models used to describe long memory phenomena.¹ Section 1 briefly defines the concept of fractional integration, shows the fundamental properties and provides a short summary of the estimation methods. Section 2 consists of a survey of their extensions in order to model long-term cycles.     

Rewrites of an Expert System—Lessons Learned

One component of the 1986 Tax Law was to require taxpayers to file information returns on magnetic media if the quantity to be filed was sufficiently large. A waiver from this filing requirement was possible under hardship and other criteria, and could be obtained by filing a form with the Internal Revenue Service (IRS). Initially, the processing of waiver requests was accomplished manually by several relatively high-level analytical personnel. The IRS's Artificial Intelligence Laboratory (AI Lab) created an Expert System to automate the process. An initial prototype was developed in OPS5+, an AI language, and the system was used on all waiver requests for Forms 1099 for Tax Year 1987, demonstrating feasibility and capability. The system was expanded in the following year, and used on waiver requests for all form types. For Tax Year 1989 the system was rewritten in LEVEL5, so that it could be more easily maintained by in-house personnel. However, implementation problems forced a rapid rewrite, using CLIPPER, a dBase III+ compiler language. This version was subsequently used for all waiver requests for Tax Years 1989 and 1990. Presently, one clerical person can handle all of the waivers. This paper deals with the reasons and ramifications of this language-shell-language transition.     

Political issues in inland waterways port development: prospects for regionalization

In the vast scientific literature on maritime transport, one theme appears neglected: the juridico-political framework in port development. We first examine how the jurisdictional control influences the allocation of resources and financial responsibilities. Second, we carefully evaluate conventional theoretical explanations of the process of port development as it generates important consequences on port policy formulation. We suggest that the concept of the port transition needs to be positioned within a new paradigm of the regional economy. Third, by focusing on three case studies namely France, China and Canada, we provide an understanding of institutional structure and how they reflect tendencies in port development. We then investigate regional flows, particularly the role of offshore, inshore and coastal traffic. Fourth, we present policy options for regionalization of ports. Fifth, we explore the regional elements of the port transition and provide an appreciation of the new role of the State in port development policies. The paper concludes on the adoption of new paradigm in port development strategies.     

The theory of double jeopardy

This paper discusses the relevance of the behavioral theory of “double jeopardy,” developed by a sociologist, to the prediction of aggregate consumer behavior. The author describes the testing of this relationship by the use of national consumer panel data and more than a quarter-million purchases. He concludes that the more popular a brand becomes, the more loyal to it will be its buyers.     

Ranking of information systems in agency models: an integral condition

Summary. We provide a condition for ranking of information systems in agency problems. The condition has a straightforward economic interpretation in terms of the sensitivity of a cumulative distribution with respect to the agent's effort. The criterion is shown to be equivalent to the mean preserving spread condition on the likelihood ratio distributions. Received: November 10, 1999; revised version: February 17, 2000     

Gender Diversity in Corporate Governance and Top Management

This article examines whether and how the participation of women in the firm’s board of directors and senior management enhances financial performance. We use the Fama and French (1992, 1993) valuation framework to take the level of risk into consideration, when comparing firm performances, whereas previous studies used either raw stock returns or accounting ratios. Our results indicate that firms operating in complex environments do generate positive and significant abnormal returns when they have a high proportion of women officers. Although the participation of women as directors does not seem to make a difference in this regard, firms with a high proportion of women in both their management and governance systems generate enough value to keep up with normal stock-market returns. These findings tend to support the policies currently being discussed or implemented in some countries and organizations to foster the advancement of women in business.     

Labour Demand Adjustment: Does Foreign Ownership Matter?

This paper examines whether multinationals differ in their employment adjustment from domestic companies, using a panel of 5,544 Belgian firms observed between 1998 and 2005. More precisely, we estimate labour adjustment costs by worker and firm types. We propose a new flexible specification that takes into account the role of firm size in adjustment costs. Our results indicate that adjusting white‐collar employment is around half as costly for multinational firms (MNFs) as for domestic firms of the same size. The remaining differential in adjustment costs between MNFs and domestic firms might result, among other things, from multinationals' stronger bargaining power.