ppxscal/embedding_network huggingface dataset:
Essays on neighborhood effects and spatial diffusion: evidence from online grocery retailing
Authors: David R. Bell
Venue:  (2005)

For a traditional retailer, the size of the customer pool can evolve over time but is largely bounded in space. In contrast, an Internet retailer with the appropriate shipping infrastructure can draw customers from a wide-ranging geographical area (e.g., the entire United States). Insight into the process of customer base evolution is therefore of considerable importance for managers and researchers alike. In this dissertation, we examine the space-time sequencing of customer orders and the individual trial decision for customers shopping at an Internet grocery retailer (Netgrocer.com). Drawing on literature in economics, marketing and sociology, we conjecture that the trial decision may be subject to neighborhood effects. That is, exposure to the actions of proximate others&mdash;either through direct social interaction or passive observation&mdash;influences the trial decision of individuals who have yet to experience the service. We focus on obtaining answers to the following general research questions: (1) Is there evidence that neighborhood effects are helping to generate the observed pattern of customer evolution in space and time? (2) If so, what is the economic impact of neighborhood effects on space-time diffusion? (3) Are the neighborhood effects absent for repeat purchase decisions? These questions are examined in two separate essays. In the first essay, we develop a discrete-time hazard model in which consumer trial decisions arise from utility-maximizing behavior. In the second essay, a spatial mixture modeling framework is developed. Each essay addresses substantive implications for customer base evolution in an Internet retailing context. All models are calibrated on a unique dataset that combines: (1) a complete transaction history from Netgrocer.com, (2) US Census information, and (3) region-level retail structure data. Geographic Information System (GIS) analysis is employed to create an alternative representation of spatial interactions.
Virtual teams combining mobile devices with web-based communication on group decision making
Authors: Starr Roxanne Hiltz
Venue:  (2004)

Organizations have moved from a face-to-face team environment to a virtual team environment using communication technology during the last decade. More and more workers use asynchronous tools (including email, discussion groups, information sharing tools, and group calendaring systems), and synchronous tools, such as instant messaging and web-based chatting features, to coordinate and share information with people within and outside of organizations. This empirical study on how virtual teams work, integrating mobile devices with web-based group communication for decision-making tasks, examines which technologies and communication modes are the best for distributed group teamwork, and, mainly, what are the predictive characteristics making mobile group communication successful. This thesis includes research motivations and research questions, followed by a theoretical framework based on existing theories and an extensive literature review, methodology, and data analysis. The last part is the results with conclusions and contributions of this study. Further work should focus on dispersed virtual teamwork using different communication modes and technologies depending on the characteristics of the tasks and members, and organizational cultures.
Quasi-random testing
Authors: Tsong Yueh Chen, Robert Merkel
Venue: Proceedings of the 20th IEEE/ACM international Conference on Automated software engineering (2005)

Quasi-random sequences, also known as low-discrepancy or low-dispersion sequences, are sequences of points in an n-dimensional unit hypercube. These sequences have the property that points are spread more evenly throughout the cube than random point sequences, which result in regions where there are clusters of points and others that are sparsely populated. Based on the observation that program faults tend to lead to contiguous failure regions within a program's input domain, and that an even spread of random tests enhances the failure detection effectiveness for certain failure patterns, we examine the use of these sequences as a replacement for random sequences in automated testing.The limited number of quasi-random sequences available from the standard algorithms poses significant practical problems for use when testing real programs, and especially for evaluating its effectiveness. We examine the use of randomised quasi-random sequences, which are permuted in a nondeterministic fashion but still retain their low discrepancy properties, to overcome this problem, and show that testing using randomised quasi-random sequences is often significantly more effective than random testing.
Parking systems analysis: an overview
Authors: Raymond H. Ellis, John C. Bennett, Paul R. Rassam
Venue: ACM SIGSIM Simulation Digest (1974)

The availability and quality of parking plays an important role in shaping the overall service provided by the highway system. The usefulness of the automobile can be impaired if the driver is unable to find convenient and reasonably priced parking in the vicinity of his final destination. Further, the design of the parking system can significantly influence the quality of the environment, particularly the ambient air quality and noise levels in high-density areas such as the central business district (CBD). Similarly, the choice of mode of access to transit, the selection of a transit station, and the difficulty of driving and parking in the CBD are critical inputs to modal choice and transit network evaluation models. In this context, the parking system constitutes an important element of the urban transportation system.
Finding Rare Data Objects in P2P File-Sharing Systems
Authors: Wai Gen Yee, Dongmei Jia, Ophir Frieder
Venue: Proceedings of the Fifth IEEE International Conference on Peer-to-Peer Computing (2005)

Peer-to-peer file-sharing systems have hundreds of thousands of users sharing petabytes of data, however, their search functionality is limited. In general, query results contain many references to the same data object. These references are grouped, and the size of the group ¿ the number of references it contains ¿ is the typical ranking metric. Although group size is effective in finding popular data, it works poorly for rare, less popular data. Other ranking functions, such as precision and cosine similarity, are more appropriate in this case. We show the significant performance benefitin finding rare data using these ranking functions through extensive simulation.
Fault-Tolerance in Distributed Query Processing
Authors: Jim Smith, Paul Watson
Venue: Proceedings of the 9th International Database Engineering & Application Symposium (2005)

Fault-tolerance has long been a feature of database systems, with transactions supporting the structuring of applications so as to ensure continuation of updating applications in spite of machine failures. For read-only queries the perceived wisdom has been that support for fault-tolerance is too expensive to be worthwhile. Distributed query processing is coming to be seen as a promising way of implementing applications that combine structured data and analysis operations in dynamic distributed settings such as computational grids. Such a query may be long-running and having to redo the whole query after a failure may cause problems (e.g. if the result may trigger business or safety critical activities). This work describes and evaluates a new scheme for adding fault-tolerance to distributed query processing through a rollback-recovery mechanism. The high level expression of user requests in a physical algebra offers opportunities for tuning the fault-tolerance provision so as to reduce the cost, and give better performance than employment of generic fault-tolerance mechanisms at the lowest level of query processing. This paper outlines how the publicly-available OGSA-DQP computational grid-based distributed query processing system can be modified to include support for fault-tolerance and presents a performance evaluation which includes measurements of the cost of both protocol overheads and rollback-recovery, for a set of example distributed queries.
Web Prediction Using Online Support Vector Machine
Authors: Zhili Zhang, Changgeng Guo, Shu Yu, De Yu Qi, Songqian Long
Venue: Proceedings of the 17th IEEE International Conference on Tools with Artificial Intelligence (2005)

In this paper, a SVM-based online learning algorithm is proposed and applied to the problem of web prediction. A method to construct an Online LS-SVM multi-class Learning Model has been presented. This method is able to capture the inherent sequentiality of web visits and successfully predict the future accesses. The experimental results show the effective performance of our method.
Choreogenetics: the generation of choreographic variants through genetic mutations and selection
Authors: François-Joseph Lapointe
Venue: Proceedings of the 2005 workshops on Genetic and evolutionary computation (2005)

In this paper, a genetic algorithm is introduced to generate variants of a choreographic sequence, which are then selected using different criteria. The mutation phase of the algorithm applies six types of mutations on single sequences, as well as four types of mutations on multiple sequences. Six different selection criteria are also distinguishable to assess the fitness of the sequences. An application of Choreogenetics is presented to illustrate the performance of the method for the generation of an aesthetic choreography.
A Generative Style-driven Framework for Software Architecture Design
Authors: Jun KONG, Kang ZHANG, Jing DONG, Guanglei SONG
Venue: Proceedings of the 29th Annual IEEE/NASA on Software Engineering Workshop (2005)

Compared with texts, graphs are more intuitive to express comparative and structural information. Many graphical approaches, however, lack a formal basis for precise specifications in the design. This paper proposes a generative style-driven framework for software architecture specification based on a visual language formalism. In this framework, the designer uses graphical notations to define architectural styles. Given the graphical specifications, a visual language generator, i.e. a meta-tool, can automatically generate a specific design environment, which is suitable for the users without any knowledge of formal methods to directly manipulate software architectures by drawing box-line graphs. The graph transformation engine underlying the design environment can automatically validate structural integrity and reveal the hierarchical structure of a user-defined software architecture.
Design and evaluation of a list-gathering tool in a web-based collaborative environment
Authors: Starr Roxanne Hiltz, Murray Turoff
Venue:  (2003)

This research focuses on how to build a &ldquo;list&rdquo; structure to combine individual items of information into some sort of structure that converts the individual items of information into a structure of knowledge relative to the problem. Software was designed to provide relationships among and comparisons of the contributions in a &ldquo;list&rdquo; structure, so that individual members of a group process will be able to understand the contributions of information made by the group as a whole. A List Gathering Tool was designed and implemented, which is one component in a Web-based Social Decision Support System (SDSS) Toolkit. Then, a two-by-two factorial design (list tool support vs. no list tool support, and voting tool support vs. no voting tool support, respectively) controlled experiment and several field studies were carried out to assess the effects of this List Gathering Tool in a group problem solving process. Overall, the evaluation results are encouraging. The utilization of the List Gathering Tool or the SDSS Toolkit does tend to improve the ability to discover valid alternatives. An additional set of field trials illustrated how the SDSS Toolkit can be utilized in a collaborative learning environment to improve teaching and students' learning experience. This system will also work for very practical applications in large group settings.
A Hybrid Forecasting Methodology using Feature Selection and Support Vector Regression
Authors: Jose Guajardo, Jaime Miranda, Richard Weber
Venue: Proceedings of the Fifth International Conference on Hybrid Intelligent Systems (2005)

Various techniques have been proposed to forecast a given time series. Models from the ARIMA family have been successfully used as well as regression approaches based on e.g. linear, non-linear regression, neural networks, and Support Vector Machines. What makes the difference in many real-world applications, however, is not the technique but an appropriated forecasting methodology. Here we present such a methodology for the regressionbased forecasting approach. A hybrid system is presented that iteratively selects the most relevant features and constructs the best regression model given certain criteria. We present a particular technique for feature selection as well as for model construction. The methodology, however, is a generic one providing the opportunity to employ alternative approaches within our framework.
Simulation of a computer communication network with GPSS & SIMSCRIPT: report on a case-study project for students
Authors: H. Kirmes, W. Kreutzer, J. Niedereichholz, C. Wentzel
Venue: ACM SIGSIM Simulation Digest (1981)

The results and experiences of a simulation case-study conducted in a seminar for advanced students of applied computer science are reported.A simulation model of a hypothetical teleprocessing network linking a number of universities to a central computer facility was programmed in various versions by 2 groups of students, using the GPSS1100 and SIMSCRIPT II.5 simulation programming languages.After a brief description of the environment and the problem definitions, the basic modelling philosophies of both approaches are contrasted and compared. The simulation results show a surprising similarity. This must, however, at least in part be attributed to the relative "courseness" of the problem situation. Both models arrived at the "best" line-configuration for the data transmission network. The utilization-figures for single lines do not differ by more than 1%.A comparison of the computational resources used shows a marked difference in favour of the SIMSCRIPT models.Various conceptual and implementational problems faced by the programming groups are summarized and discussed.The report closes with the observation that the advantages and shortcomings experienced by using these 2 different modelling approaches and languages can be generalized and are certainly representative and inevitable reflections of basic trade-offs between user-efficiency & conceptual congruence on the one, and processor-efficiency, flexibility & representational power on the other hand.
Documentation in the college environment
Authors: Edward M. Burghard
Venue: ACM SIGDOC Asterisk Journal of Computer Documentation (1976)

It is an unfortunate, but true fact, that many student programs possess the same quality of vagueness as the book in the above quote. It could take years to decipher exactly what the code means. I say this is unfortunate because these same students are the source for future business programmers. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
An answer to an open problem on triangular norms
Authors: Yao Ouyang, Jun Li
Venue: Information Sciences: an International Journal (2005)

In this paper, we shall give an example to show that an open problem of Fodor on triangular norm, which is collected by Klement et al. in "Problems on triangular norms and related operators" (Fuzzy Sets and Systems 145 (2004), 471-479), has a negative solution.
Probabilistic ensemble simplified fuzzy ARTMAP for sonar target differentiation
Authors: Kiong Loo, Augustine Law, W. S. Lim, M. V. C. Rao
Venue: Neural Computing and Applications (2006)

This study investigates the processing of sonar signals with ensemble neural networks for robust recognition of simple objects such as plane, corner and trapezium surface. The ensemble neural networks can differentiate the target objects with high accuracy. The simplified fuzzy ARTMAP (SFAM) and probabilistic ensemble simplified fuzzy ARTMAP (PESFAM) are compared in terms of classification accuracy. The PESFAM implements an accurate and effective probabilistic plurality voting method to combine outputs from multiple SFAM classifiers. Five benchmark data sets have been used to evaluate the applicability of the proposed ensemble SFAM network. The PESFAM achieves good accuracy based on the twofold cross-validation results. In addition, the effectiveness of the proposed ensemble SFAM is delineated in sonar target differentiation. The experiments demonstrate the potential of PESFAM classifiers in offering an optimal solution to the data-ordering problem of SFAM implementation and also as an intelligent classification tool in mobile robot application.
Dirichlet enhanced relational learning
Authors: Zhao Xu, Volker Tresp, Kai Yu, Shipeng Yu, Hans-Peter Kriegel
Venue: Proceedings of the 22nd international conference on Machine learning (2005)

We apply nonparametric hierarchical Bayesian modelling to relational learning. In a hierarchical Bayesian approach, model parameters can be "personalized", i.e., owned by entities or relationships, and are coupled via a common prior distribution. Flexibility is added in a nonparametric hierarchical Bayesian approach, such that the learned knowledge can be truthfully represented. We apply our approach to a medical domain where we form a nonparametric hierarchical Bayesian model for relations involving hospitals, patients, procedures and diagnosis. The experiments show that the additional flexibility in a nonparametric hierarchical Bayes approach results in a more accurate model of the dependencies between procedures and diagnosis and gives significantly improved estimates of the probabilities of future procedures.
Thermal-Aware Test Scheduling and Hot Spot Temperature Minimization for Core-Based Systems
Authors: Chunsheng Liu, Kugesh Veeraraghavant, Vikram Iyengar
Venue: Proceedings of the 20th IEEE International Symposium on Defect and Fault Tolerance in VLSI Systems (2005)

Chip overheating has become a critical problem during test of today's complex core-based systems. In this paper, we address the overheating problem by incorporating thermal constraints in the test scheduling of corebased systems. We propose two algorithms for which the objective is to spread heat more evenly over the chip and reduce hot spots. The first uses the layout information to guide test scheduling, while the second relies on a progressive weighting mechanism. Experimental results show that the proposed thermal-constrained methods can not only guarantee a thermal-safe test schedule, but also reduce hot spot temperatures, leading to a balanced thermal distribution across the chip during test.
Building Wide-Area Collaborative Applications on top of Structured Peer-to- Peer Overlays
Authors: Carles Pairot, Pedro Garcia, Ruben Mondejar, Antonio F. Gomez Skarmeta
Venue: Proceedings of the 14th IEEE International Workshops on Enabling Technologies: Infrastructure for Collaborative Enterprise (2005)

In this paper we present p2pCM, a new distributed component-oriented model aimed to wide-area environments. Our model offers traditional component services like naming, activation, event notifications, and persistence on top of a structured peer-to-peer overlay. We benefit from the peer-to-peer substrate to implement these services in a decentralized and efficient way. The innovative contributions of our approach are a lightweight distributed container model, an adaptive component activation mechanism, which takes into account network locality, and a decentralized component location and deployment service. We focus on how the services provided by p2pCM can be used to implement essential computer-supported cooperative work (CSCW) services, like shared session management, awareness and coordination policies, and show a sample application which uses them. We believe that all of the features our component-oriented model provides can be very promising for the development of future wide-area distributed CSCW applications.
Noise-Resistant Fitting for Spherical Harmonics
Authors: Ping-Man Lam, Chi-Sing Leung, Tien-Tsin Wong
Venue: IEEE Transactions on Visualization and Computer Graphics (2006)

Spherical harmonic (SH) basis functions have been widely used for representing spherical functions in modeling various illumination properties. They can compactly represent low-frequency spherical functions. However, when the unconstrained least square method is used for estimating the SH coefficients of a hemispherical function, the magnitude of these SH coefficients could be very large. Hence, the rendering result is very sensitive to quantization noise (introduced by modern texture compression like S3TC, IEEE half float data type on GPU, or other lossy compression methods) in these SH coefficients. Our experiments show that, as the precision of SH coefficients is reduced, the rendered images may exhibit annoying visual artifacts. To reduce the noise sensitivity of the SH coefficients, this paper first discusses how the magnitude of SH coefficients affects the rendering result when there is quantization noise. Then, two fast fitting methods for estimating the noise-resistant SH coefficients are proposed. They can effectively control the magnitude of the estimated SH coefficients and, hence, suppress the rendering artifacts. Both statistical and visual results confirm our theory.
Matrix rounding with respect to small submatrices
Authors: Benjamin Doerr
Venue: Random Structures Algorithms (2006)

We show that any real valued matrix A can be rounded to an integer one B such that the error in all 2 &times; 2 (geometric) submatrices is less than 1.5, that is, we have |aij - bij| < 1 and $|\sum_{k = i}^{i+1}\sum_{\ell = j}^{j+1} (a_{k\ell} - b_{k\ell})| < 1.5$ for all i,j. &copy; 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2006
Building 21st Century Enterprises
Authors: Raymond T. Yeh
Venue: Proceedings of the Third ACIS Int'l Conference on Software Engineering Research, Management and Applications (2005)

This talk will explore how 21st century enterprise must do in order to survive the accelerated changes globally and compete effectively. There are three major aspects that an enterprise needs to follow, namely;