OpenRaiser/Intern-Atlas huggingface dataset:
An interactive semantics of logic programming
Venue: arXiv cs.LO 2001
Year: 2001

We apply to logic programming some recently emerging ideas from the field of reduction-based communicating systems, with the aim of giving evidence of the hidden interactions and the coordination mechanisms that rule the operational machinery of such a programming paradigm. The semantic framework we have chosen for presenting our results is tile logic, which has the advantage of allowing a uniform treatment of goals and observations and of applying abstract categorical tools for proving the results. As main contributions, we mention the finitary presentation of abstract unification, and a concurrent and coordinated abstract semantics consistent with the most common semantics of logic programming. Moreover, the compositionality of the tile semantics is guaranteed by standard results, as it reduces to check that the tile systems associated to logic programs enjoy the tile decomposition property. An extension of the approach for handling constraint systems is also discussed.
aspps --- an implementation of answer-set programming with propositional schemata
Venue: arXiv cs.AI 2001
Year: 2001

We present an implementation of an answer-set programming paradigm, called aspps (short for answer-set programming with propositional schemata). The system aspps is designed to process PS+ theories. It consists of two basic modules. The first module, psgrnd, grounds an PS+ theory. The second module, referred to as aspps, is a solver. It computes models of ground PS+ theories.
TeXmacs interfaces to Maxima, MuPAD and REDUCE
Venue: arXiv cs.SC 2001
Year: 2001

GNU TeXmacs is a free wysiwyg word processor providing an excellent typesetting quality of texts and formulae. It can also be used as an interface to Computer Algebra Systems (CASs). In the present work, interfaces to three general-purpose CASs have been implemented.
The Cactus Worm: Experiments with Dynamic Resource Discovery and Allocation in a Grid Environment
Venue: arXiv cs.DC 2001
Year: 2001

The ability to harness heterogeneous, dynamically available "Grid" resources is attractive to typically resource-starved computational scientists and engineers, as in principle it can increase, by significant factors, the number of cycles that can be delivered to applications. However, new adaptive application structures and dynamic runtime system mechanisms are required if we are to operate effectively in Grid environments. In order to explore some of these issues in a practical setting, we are developing an experimental framework, called Cactus, that incorporates both adaptive application structures for dealing with changing resource characteristics and adaptive resource selection mechanisms that allow applications to change their resource allocations (e.g., via migration) when performance falls outside specified limits. We describe here the adaptive resource selection mechanisms and describe how they are used to achieve automatic application migration to "better" resources following performance degradation. Our results provide insights into the architectural structures required to support adaptive resource selection. In addition, we suggest that this "Cactus Worm" is an interesting challenge problem for Grid computing.
Links tell us about lexical and semantic Web content
Venue: arXiv cs.IR 2001
Year: 2001

The latest generation of Web search tools is beginning to exploit hypertext link information to improve ranking\cite{Brin98,Kleinberg98} and crawling\cite{Menczer00,Ben-Shaul99etal,Chakrabarti99} algorithms. The hidden assumption behind such approaches, a correlation between the graph structure of the Web and its content, has not been tested explicitly despite increasing research on Web topology\cite{Lawrence98,Albert99,Adamic99,Butler00}. Here I formalize and quantitatively validate two conjectures drawing connections from link information to lexical and semantic Web content. The clink-content conjecture states that a page is similar to the pages that link to it, i.e., one can infer the lexical content of a page by looking at the pages that link to it. I also show that lexical inferences based on link cues are quite heterogeneous across Web communities. The link-cluster conjecture states that pages about the same topic are clustered together, i.e., one can infer the meaning of a page by looking at its neighbours. These results explain the success of the newest search technologies and open the way for more dynamic and scalable methods to locate information in a topic or user driven way.
Computational Geometry Column 42
Venue: arXiv cs.CG 2001
Year: 2001

A compendium of thirty previously published open problems in computational geometry is presented.
Conceptualising Regulatory Change - Explaining Shifts in Telecommunications Governance
Venue: arXiv cs.CY 2001
Year: 2001

Drawing on perspectives from telecommunications policy and neo-Gramscian understandings of international political economy, this paper offers an explanation and analysis of the shifting patterns of regulation which have been evident in the telecommunications sector in recent years. It aims to illustrate explain and explore the implications of the movement of regulatory sovereignty away from the nation-state, through regional conduits, to global organisations in the crystallisation of a world system of telecommunications governance. Our central argument is that telecommunications governance has evolved from a regulatory arena characterised, in large part, by national diversity, to one wherein a more convergent global multilayered system is emerging. We suggest that the epicentre of this regulatory system is the relatively new World Trade Organisation (WTO). Working in concert with the WTO are existing well-established nodes regulation. In further complement, we see regional regulatory projects, notably the European Union (EU), as important conduits and nodes of regulation in the consolidation of a global regulatory regime. By way of procedure, we first explore the utility of a neo-Gramscian approach for understanding the development of global regulatory frameworks. Second, we survey something of the recent history - and, in extension, conventional wisdom - of telecommunications regulation at national and regional levels. Third, we demonstrate how a multilayered system of global telecommunications regulation has emerged centred around the regulatory authority of the WTO. Finally, we offer our concluding comments.
Routing Permutations in Partitioned Optical Passive Star Networks
Venue: arXiv cs.DC 2001
Year: 2001

It is shown that a POPS network with g groups and d processors per group can efficiently route any permutation among the n=dg processors. The number of slots used is optimal in the worst case, and is at most the double of the optimum for all permutations p such that p(i)<>i for all i.
Relevant Knowledge First - Reinforcement Learning and Forgetting in Knowledge Based Configuration
Venue: arXiv cs.AI 2001
Year: 2001

In order to solve complex configuration tasks in technical domains, various knowledge based methods have been developed. However their applicability is often unsuccessful due to their low efficiency. One of the reasons for this is that (parts of the) problems have to be solved again and again, instead of being "learnt" from preceding processes. However, learning processes bring with them the problem of conservatism, for in technical domains innovation is a deciding factor in competition. On the other hand a certain amount of conservatism is often desired since uncontrolled innovation as a rule is also detrimental. This paper proposes the heuristic RKF (Relevant Knowledge First) for making decisions in configuration processes based on the so-called relevance of objects in a knowledge base. The underlying relevance-function has two components, one based on reinforcement learning and the other based on forgetting (fading). Relevance of an object increases with its successful use and decreases with age when it is not used. RKF has been developed to speed up the configuration process and to improve the quality of the solutions relative to the reward value that is given by users.
Crisis of Public Utility Deregulation and the Unrecognized Welfare State
Venue: arXiv cs.CY 2001
Year: 2001

Successful achievement of public policies requires satisfaction of conditions affecting political feasibility for policy adoption and maintenance as well as economic viability of the desired activity or enterprise. This paper discusses the difficulties of satisfying these joint constraints given the legacy of the common law doctrines of "just price" and "businesses affected with a public interest." In this regard, it is helpful to view traditional public utility regulation as a form of welfare state regulation, as it suffers from similar political problems from policy retrenchment. The retrenchment problems are examined in the context of the electricity crisis in California as well as the passage and implementation of the Telecommunications Act of 1996. As expected, retrenchment from low residential retail rates - the most universalistic benefit for customers - faces the greatest political resistance. The societal trade-offs between monopoly and competition must be reexamined in light of the greater instability and political difficulties under a deregulatory regime.
Product Cycle, Wintelism, and Cross-national Production Networks (CPN) for Developing Countries-- China's Telecom Manufacturing Industry as A Case
Venue: arXiv cs.CY 2001
Year: 2001

Focusing on the telecom manufacturing industry in China, this paper contends that the existing literature needs to be expanded in order to explain the Chinese case. First, product cycle theory could be applied to explain multinational corporations' strategies of importing and localizing their products in China in order to take advantage of lower labor costs and often more significantly to break barriers to the Chinese market. Second, there are no significant indicators pointing to local multinational subsidiaries and indigenous manufacturers serving as a substantial part of the cross-national production networks in the global telecom industry yet, although there are some signs of potential development. Third, the success of "Wintelism" and the maturity of cross-national production networks in the global market have had significant impacts on China's indigenous industry.
Price Increases from Online Privacy
Venue: arXiv cs.CY 2001
Year: 2001

Consumers value keeping some information about them private from potential marketers. E-commerce dramatically increases the potential for marketers to accumulate otherwise private information about potential customers. Online marketers claim that this information enables them to better market their products. Policy makers are currently drafting rules to regulate the way in which these marketers can collect, store, and share this information. However, there is little evidence yet either of consumers' valuation of their privacy or of the benefits they might reap through better target marketing. We provide a framework for measuring a portion of the benefits from allowing marketers to make better use of consumer information. Target marketing is likely to reduce consumer search costs, improve consumer product selection decisions, and lower the marketing costs of goods sold. Our model allows us to estimate the value to consumers of only the latter, price reductions from more efficient marketing.
Commonalities: The R.E.A. and High-Speed Rural Internet Access
Venue: arXiv cs.CY 2001
Year: 2001

This paper explores commonalities between the creation of the Rural Electrification Administration and the similar dilemma of providing an affordable infrastructure for high-speed Internet access in places where profit incentives do not exist. In the case of the R.E.A., the necessity for an aggressive federal initiative to wire rural America, where the market for electricity had failed, is revisited as the missing incentives are identified and explored. We then examine the incentive-poor similarities between rural electrification and rural high-speed Internet access through how consumers currently and prospectively gain access to broadband Internet service. The regulatory environment created by the Telecommunications Act of 1996 and the Federal Communications Commission is considered. Although the FCC is required (Section 254.b.3) to take regulatory measures to ensure comparable and affordable access to the Internet for all Americans, the historical similarities and comparative analysis of rural electrification and high-speed Internet access suggests the goal of universal service is unlikely to be met in the near future. Regulatory disincentives to build such networks are present, driven in part by market realities and in part by competitive restrictions in the Telecommunications Act of 1996. Finally, we pose the question of whether a federal effort equivalent to the R.E.A. is needed to ensure that residents of sparsely populated areas, like their predecessors in the 1930s, are not comparatively disadvantaged in the first decades of the 21st century. The paper concludes with a proposal to accelerate the deployment of broadband infrastructure in rural America.
Lead, Follow, or Go Your Own Way: Empirical Evidence Against Leader-Follower Behavior in Electronic Markets
Venue: arXiv cs.CY 2001
Year: 2001

Low search costs in Internet markets can be used by consumers to find low prices, but can also be used by retailers to monitor competitors' prices. This price monitoring can lead to price matching, resulting in dampened price competition and higher prices in some cases. This paper analyzes price data for 316 bestselling, computer, and random book titles gathered from 32 retailers between August 1999 and January 2000. In contrast to previous studies we find no evidence of leader-follow behavior for the vast majority of retailers we study. Further, the few cases of leader-follow behavior we observe seem to be associated with managerial convenience as opposed to anti-competitive behavior. We offer a methodology that can be used by future academic researchers or government regulators to check for anti-competitive price matching behavior in future time periods or in additional product categories.
Civic Engagement among Early Internet Adopters: Trend or Phase?
Venue: arXiv cs.CY 2001
Year: 2001

This paper brings evidence to bear on the question of the long-term effects of Internet diffusion on civic engagement in geographic communities. It draws on findings from survey data collected in four U.S. towns and cities in fall 2000 where community computer networking is established. The study shows that early adopters of the Internet are more likely to engage in civic activities and to have higher levels of community involvement than later adopters. Further, early adopters are more likely to use the Internet to increase their community involvement and political participation. Later adopters in all four sites show less involvement in their local community and less interest in political activity and information, online or offline. These findings reinforce those of the Kohut (1999) study showing that later adopters are less civic minded and more interested than early adopters in consumer and commercial applications, such as shopping and entertainment. The evidence in these four sites is consistent with earlier findings in Blacksburg, Virginia (Kavanaugh, 2000; Patterson and Kavanaugh, 2001; Kavanaugh and Patterson, 2001) and other studies of early innovation adopters (Rogers, 1983; Kohut, 1999; Valente, 1995, among others). The results reported in this paper lend weight to the argument that increases in civic engagement and community involvement are due primarily to the behavior of early adopters, making such increases a phase, not a trend. As later adopters come on line, use of the Internet for community involvement or civic engagement decreases. In the long term, we can expect that Internet access may have only a modest effect on community involvement and civic engagement in geographic communities.
Comparison of Wireless Standards-Setting --United States Versus Europe
Venue: arXiv cs.CY 2001
Year: 2001

When decisions about developing standards are left to individual firms, there are many advantages including a flexible response to market evolution, accommodation to rapid technology change, and avoidance of costly coordination. However, the market process does not necessarily lead to compatible standards, especially when there is no clear market dominator. Standards Institutions generally facilitate better communication among market participants, which may discourage early and/or primitive incompatible standards to emerge in the market. However, expenditures on institutional standards-setting can lead to diminishing returns, or even be counter-productive because institutional standards usually take longer to produce and are slower to respond to technology development. Government agencies can specify compulsory standards to avoid incompatibility. In addition, governments can tie their policy on standardization closely with their industrial, trade, and/or regulatory policies. However, many exogenous factors handicap a government's effective involvement. Government often fails to respond to the dynamics of technology development and consumer demand, and to pick up the "right technology". This study first discusses why two different models have emerged in the two regions. It then examines outcomes and implications of the two models, including impacts on domestic service deployment, global trade competition, technology innovations, and strategies of multinational corporations. The goal is to conduct an empirical comparison between the two contrasting models.
Bigger May Not Be Better: An Empirical Analysis of Optimal Membership Rules in Peer-To-Peer Networks
Venue: arXiv cs.CY 2001
Year: 2001

Peer to peer networks will become an increasingly important distribution channel for consumer information goods and may play a role in the distribution of information within corporations. Our research analyzes optimal membership rules for these networks in light of positive and negative externalities additional users impose on the network. Using a dataset gathered from the six largest OpenNap-based networks, we find that users impose a positive network externality based on the desirability of the content they provide and a negative network externality based on demands they place on the network. Further we find that the marginal value of additional users is declining and the marginal cost is increasing in the number of current users. This suggests that multiple small networks may serve user communities more efficiently than single monolithic networks and that network operators may wish to specialize in their content and restrict membership based on capacity constraints and user content desirability.
Spectrum auctions, pricing and network expansion in wireless telecommunications
Venue: arXiv cs.CY 2001
Year: 2001

This paper examines the effects of licensing conditions, in particular of spectrum fees, on the pricing and diffusion of mobile communications services. Seemingly exorbitant sums paid for 3G licenses in the UK, Germany in 2000 and similarly high fees paid by U.S. carriers in the re-auctioning of PCS licenses early in 2001 raised concerns as to the impacts of the market entry regime on the mobile communications market. The evidence from the GSM and PCS markets reviewed in this paper suggests that market entry fees do indeed influence the subsequent development of the market. We discuss three potential transmission channels by which license fees can influence the price and quantity of service sold in a wireless market: an increase in average cost, an increase in incremental costs, and impacts of sunk costs on the emerging market structure. From this conceptual debate, an empirical model is developed and tested using cross-sectional data for the residential mobile voice market. We utilize a structural equation approach, modeling the supply and demand relationships subject to the constraint that supply equals demand. The results confirm the existence of a positive effect of license fees on the cost of supply. However, we also find that higher market concentration has a positive effect on the overall supply in the market, perhaps supporting a Schumpeterian view that a certain degree of market concentration facilitates efficiency.
The Consumer Product Selection Process in an Internet Age: Obstacles to Maximum Effectiveness & Policy Options
Venue: arXiv cs.CY 2001
Year: 2001

Intermediaries, like real estate agents, Consumer Reports, and Zagats, have long helped buyers to identify their most suitable options. Now, the combination of databases and the Internet enables them to serve consumers dramatically more effectively. This article begins by offering a three-part framework for understanding the evolving forms of selection assistance. It then focuses on numerous potential obstacles that could prevent shoppers from enjoying the full benefits of these developing technologies. While concluding that adjustments to business strategies and the enforcement of existing laws can effectively overcome most of these impediments, the article identifies several areas where proactive government action may be desirable, such as to prevent the emergence of anticompetitive entry barriers.
Prospects for Improving Competition in Mobile Roaming
Venue: arXiv cs.CY 2001
Year: 2001

The ability to make international roaming calls is of increasing importance to customers in Europe. This contrasts with various complaints that retail prices of roaming calls are rigid and excessive. The focus if the paper is on wholesale roaming, which is the prime determinant of retail roaming prices. The paper analyses the structural conditions of wholesale roaming markets that have impaired incentives to competition, namely high combined market share of the two leading GSM 900 operators combined with second mover disadvantages for new entrant GSM 1800 operators, and demand externalities. The paper argues that a number of developments are under way that are likely to modify this situation in the future. With the introduction of SIM over-the-air programming, home mobile operators will be able to direct customers to networks with the lowest charges. As dual mode handsets become ubiquitous and as new entrant GSM 1800 operators reach nationwide coverage, second-mover disadvantages will disappear. Given the relatively small roaming volumes that GSM 1800 operators currently provide, they should have an incentive to lower charges in exchange for preferred roaming status. On the demand side of wholesale roaming markets, it will be the larger GSM 900 operators, and in particular those with a pan-European footprint, that will ask for lower charges in exchange for preferred roaming status. This could discriminate against mobile operators in downstream retail markets that do not have a pan-European footprint and that lack the bargaining power. However, arbitrage by roaming brokers, new entry and wider geographical markets on the retail roaming level will work against this.
Digital Color Imaging
Venue: arXiv cs.CV 2001
Year: 2001

This paper surveys current technology and research in the area of digital color imaging. In order to establish the background and lay down terminology, fundamental concepts of color perception and measurement are first presented us-ing vector-space notation and terminology. Present-day color recording and reproduction systems are reviewed along with the common mathematical models used for representing these devices. Algorithms for processing color images for display and communication are surveyed, and a forecast of research trends is attempted. An extensive bibliography is provided.