ppxscal/embedding_network huggingface dataset:
Statistical detection and estimation of differential item functioning in computerized adaptive testing
Authors: Xin Feng
Venue:  (2003)

Differential item functioning (DIF) is an important issue in large scale standardized testing. DIF refers to the unexpected difference in item performances among groups of equally proficient examinees, usually classified by ethnicity or gender. Its presence could seriously affect the validity of inferences drawn from a test. Various statistical methods have been proposed to detect and estimate DIF. This dissertation addresses DIF analysis in the context of computerized adaptive testing (CAT), whose item selection algorithm adapts to the ability level of each individual examinee. In a CAT, a DIF item may be more consequential and more detrimental be cause fewer items are administered in a CAT than in a traditional paper-and-pencil test and because the remaining sequence of items presented to examinees depends in part on their responses to the DIF item. Consequently, an efficient, stable and flexible method to detect and estimate CAT DIF becomes necessary and increasingly important. We propose simultaneous implementations of online calibration and DIF testing. The idea is to perform online calibration of an item of interest separately in the focal and reference groups. Under any specific parametric IRT model, we can use the (online) estimated latent traits as covariates and fit a nonlinear regression model to each of the two groups. Because of the use of the estimated, not the true &thetas;, the regression fit has to adjust for the covariate &ldquo;measurement errors&rdquo;. It turns out that this situation fits nicely into the framework of nonlinear error-in-variable modelling, which has been extensively studied in statistical literature. We develop two bias-correction methods using asymptotic expansion and conditional score theory. After correcting the bias caused by measurement error, one can perform a significance test to detect DIF with the parameter estimates for different groups. This dissertation also discusses some general techniques to handle measurement error modelling with different IRT models, including the three-parameter normal ogive model and polytomous response models. Several methods of estimating DIF are studied as well. Large sample properties are established to justify the proposed methods. Extensive simulation studies show that the resulting methods perform well in terms of Type-I error rate control, accuracy in estimating DIF and power against both unidirectional and crossing DIF.
Entering the education arcade
Authors: Henry Jenkins, Eric Klopfer, Kurt Squire, Philip Tan
Venue: Computers in Entertainment (CIE) (2003)

Responding to social, economic, and technological trends which make games the most powerful medium for reaching young learners, The Education Arcade project, based in the MIT Comparative Media Studies Program, seeks to prototype games that teach, develop curricular materials which support existing commercial titles, and help prepare teachers to use games in the classroom. This article reports on the first three prototypes that are producing -- Supercharged! (electromagnetism), Environmental Detectives (environmental science) and Revolution (American History).
On coreferring: coreference in MUC and related annotation schemes
Authors: Kees van Deemter, Rodger Kibble
Venue: Computational Linguistics (2000)

In this paper, it is argued that "coreference" annotations, as performed in the MUC community for example, go well beyond annotation of the relation of coreference proper. As a result, it is not always clear what semantic relation these annotations are encoding. The paper discusses a number of problems with these annotations and concludes that rethinking of the coreference task is needed before the task is expanded. In particular, it suggests a division of labor whereby annotation of the coreference relation proper is separated from other tasks such as annotation of bound anaphora and of the relation between a subject and a predicative NP.
Nonpolygonal isosurface rendering for large volume datasets
Authors: James W. Durkin, John F. Hughes
Venue: Proceedings of the conference on Visualization '94 (1994)

Surface-based rendering techniques, particularly those that extract a polygonal approximation of an isosurface, are widely used in volume visualization. As dataset size increases though, the computational demands of these methods can overwhelm typically available computing resources. Recent work on accelerating such techniques has focused on preprocessing the volume data or postprocessing the extracted polygonization. Our new algorithm concentrates instead on streamlining the surface extraction process itself so as to accelerate the rendering of large volumes. The technique shortens the conventional isosurface visualization pipeline by eliminating the intermediate polygonization. We compute the contribution of the isosurface within a volume cell to the resulting image directly from a simplified numerical description of the cell/surface intersection. Our approach also reduces the work in the remaining stages of the visualization process. By quantizing the volume data, we exploit precomputed and cached data at key processing steps to improve rendering efficiency. The resulting implementation provides comparatively fast renderings with reasonable image quality.
Structure of multiple activity algorithms
Authors: John B. Johnston
Venue: Proceedings of the second symposium on Operating systems principles (1969)

In conjunction with an earlier paper, this step toward machine design based on the structure of nested-declaration pure-procedure multiple-activity algorithms describes: the declaration, flow-of-control, and some data-addressing mechanisms of such algorithms; the dynamic Saguaro-Garden data-access-providing structure of their Records of Execution ; and implementation in a segmented environment.
An Asynchronous Synthesis Toolset Using Verilog
Authors: Frank Burns, Delong Shang, Albert Koelmans, Alex Yakovlev
Venue: Proceedings of the conference on Design, automation and test in Europe - Volume 1 (2004)

We present a new CAD tool set for generating asynchronous circuits from high-level Verilog level-sensitive specifications. Initially high-level Verilog descriptions are compiled and converted into a novel intermediate Petri-net format. The intermediate format is subsequently passed to optimization tools and mapping tools where it is directly mapped into asynchronous datapath and control circuits using David Cells (DCs). Finally logic optimization tools are applied to generate speed independent (SI) circuits. The speed independent circuits generated perform well compared to circuits generated by existing asynchronous tools.
Discrete facility location and routing of obnoxious activities
Authors: P. Cappanera, G. Gallo, F. Maffioli
Venue: Discrete Applied Mathematics (2003)

The problem of simultaneously locating obnoxious facilities and routing obnoxious materials between a set of built-up areas and the facilities is addressed.Obnoxious facilities are those facilities which cause exposure to people as well as to the environment i.e. dump sites, chemical industrial plants, electric power supplier networks, nuclear reactors and so on. A discrete combined location-routing model, which we refer to as Obnoxious Facility Location and Routing model (OFLR), is defined. OFLR is a NP-hard problem for which a Lagrangean heuristic approach is presented. The Lagrangean relaxation proposed allows to decompose OFLR into a Location subproblem and a Routing subproblem; such subproblems are then strengthened by adding suitable inequalities. Based on this Lagrangean relaxation two simple Lagrangean heuristics are provided. An effective Branch and Bound algorithm is then presented, which aims at reducing the gap between the above mentioned lower and upper bounds. Our Branch and Bound exploits the information gathered while going down in the enumeration tree in order to solve efficiently the subproblems related to other nodes. This is accomplished by using a bundle method to solve at each node the Lagrangean dual. Some variants of the proposed Branch and Bound method are defined in order to identify the best strategy for different classes of instances. A comparison of computational results relative to these variants is presented.
User-directed analysis of scanned images
Authors: Steven J. Simske, Jordi Arnabat
Venue: Proceedings of the 2003 ACM symposium on Document engineering (2003)

Digital capture (scanning in all its forms, and digital photography/video recording), in providing virtually free temporary memory of captured information, allows users to "over-gather" information during capture, and then to discard unwanted material later. For cameras and video recorders, such editing largely consists of discarding images or frames in their entirety. For scanners (and high-resolution camera/video), such editing benefits from a preview capability that provides quick and reliable user-interface tools for selecting, filtering and saving specific portions of the input. Appropriate preview user interface (UI) tools ease the accessing, editing and dispatch to desired destination (archive, application, webpage, etc.) of captured information (text, tables, drawings, photos, etc.). In this paper, we present several different means for the user-directed "rapid capture" of portions of a scanned image. Specifically, we review past, present and future preview-based UI tools that allow efficient and accurate means of capture to the user. The bases of these tools, as described herein, are user-directed zoning analysis, known as "click and select", which incorporates a bottom-up zoning analysis engine; and statistics-based region classification, which allows rapid reconfiguration of region identification and clustering. We conclude with our view of the future of UI-directed capture.
Magnatune, an open music experiment
Authors: John Buckman
Venue: Linux Journal (2004)

Even if you're not reinventing the music business, what can you do to help your Web site help customers?
J2ME application-layer end-to-end security for m-commerce
Authors: Wassim Itani, Ayman Kayssi
Venue: Journal of Network and Computer Applications (2004)

This paper shows an end-to-end application-layer security solution for wireless enterprise applications using the Java 2 Platform Micro Edition (J2ME). The proposed solution uses pure Java components to provide end-to-end client authentication and data confidentiality and integrity between wireless J2ME-based clients and J2EE-based servers. This solution can be implemented with the available limited resources of a Java MIDP device, without any modification to the underlying protocols or wireless network infrastructure. A mobile banking application is used to illustrate the implementation of the proposed solution.
Modeling the meaning of transitions from and to concurrent states in UML state machines
Authors: Egon Börger, Alessandra Cavarra, Elvinia Riccobene
Venue: Proceedings of the 2003 ACM symposium on Applied computing (2003)

This paper completes the ASM models developed for UML state machines in [4, 5] providing new submachines covering also transitions from and to concurrent states in the context of event deferring and run-to-completion. Due to the modular structure of the earlier ASM models for UML state diagrams, these new submachines can be inserted there as components. The modular treatment explicitly reflects the corresponding intended "semantic variation points" of UML, thus allowing to adapt definitions given in this paper to possibly changing standardization decisions.
Combinatorial trades: a survey of recent results
Authors: Elizabeth J. Billington
Venue: DESIGNS 2002: Further computational and constructive design theory (2003)

The concept of a trade in a combinatorial structure has existed for some years now. However, in the last five years or so there has been a great deal of activity in the area. This survey paper builds upon the one by Khosrovshahi, Maimani and Torabi which appeared in Discrete Applied Mathematics (Volume 95, pp. 361-176) in 1999. In the short time since that survey appeared, the number of papers in the area has almost doubled. Trades are used in designs and latin squares; they also crop up in graph theory. In this paper the most recent work on trades is surveyed, with applications given.
Exploiting 2D concepts to achieve consistency in 3D GIS applications
Authors: Gerhard Gröger, Lutz Plümer
Venue: Proceedings of the 11th ACM international symposium on Advances in geographic information systems (2003)

This article provides a formal data model to cover many 3D applications in GIS. It is based on a 2D model and preserves the algorithmic and conceptual simplicity of the 2D case as much as possible. Integrity axioms guarantee the consistency of the model in a mathematically provable way. These axioms are effectively and efficiently checkable by automatic procedures. The model extends Digital Terrain Models by allowing for vertical walls and projections like balconies or ledges. The conceptual simplicity is due to the two-dimensional topology of the model. Thus bridges and tunnels cannot be represented; we show how to detect and handle these cases efficiently. Based on this model, spatial objects and their aggregation structures can be defined consistently.
Scandinavian versus UK research: the importance of institutional context
Authors: Carsten Sørensen
Venue: Scandinavian Journal of Information Systems (2003)

This debate outlines some of the institutional aspects of perceived research quality and the potential implications on academic behaviour across Scandinavia and the United Kingdom. In particular the paper discusses the differences in formal measurements of research output quality in the two regions considered. The paper draws upon my personal experience living and working in Scandinavia and the United Kingdom, and as such represents a subjective account. I argue that the formality of the UK Research Assessment Exercis, encourages a high degree of academic dgor and potentially discourages the willingness to innovate and expand the academic debate. Conversely, I argue that the relative lack of formality in the Scandinavian context can both encourage innovation and potentially discourage academic rigour. As an example, I highlight the emerging field of mobile informatics.
Machine independent software
Authors: P. C. Poole, W. M. Waite
Venue: Proceedings of the second symposium on Operating systems principles (1969)

The techniques of abstract machine modelling and macro processing can be used to construct software which is easily moved from one computer to another. This paper describes a system developed at the University of Colorado which has been implemented on 8 different machines, with efforts ranging from 1 man-day to 1 man-week. We feel that these techniques offer a possible solution to the "software crisis" which is plaguing the computer industry today.
Some Problems of Soil Media Ecology and Optimal Control Processes in Them
Authors: I. V. Sergienko, V. S. Deineka
Venue: Cybernetics and Systems Analysis (2003)

New multicomponent soil media ecology problems and respective optimal control problems are considered in the paper. Existence theorems for the unique optimal control are proved for all the cases considered. Computation algorithms of high-accuracy discretization are constructed for some new classes of problems with discontinuous solutions.
Causality and media synchronization control for networked multimedia games: centralized versus distributed
Authors: Yutaka Ishibashi, Shuji Tasaka
Venue: Proceedings of the 2nd workshop on Network and system support for games (2003)

This paper makes a performance comparison between a centralized control scheme and a distributed control scheme; these two schemes were previously proposed by the authors so as to preserve causality and media synchronization for networked multimedia games. In the centralized control scheme, we have a single server which carries out causality control and multiple clients which exerts media synchronization control. In the distributed control scheme, each client performs causality and media synchronization control without any server. For the performance comparison, we have carried out an experiment of a networked shooting game in which computer data, voice, and video are dealt with together.
Fast scaling algorithms for M-convex function minimization with application to the resource allocation problem
Authors: Akiyoshi Shioura
Venue: Discrete Applied Mathematics (2004)

M-convex functions, introduced by Murota (Adv. Math. 124 (1996) 272; Math. Prog. 83 (1998) 313), enjoy various desirable properties as "discrete convex functions." In this paper, we propose two new polynomial-time scaling algorithms for the minimization of an M-convex function. Both algorithms apply a scaling technique to a greedy algorithm for M-convex function minimization, and run as fast as the previous minimization algorithms. We also specialize our scaling algorithms for the resource allocation problem which is a special case of M-convex function minimization.
Quickselect and the Dickman Function
Authors: Hsien-Kuei Hwang, Tsung-Hsi Tsai
Venue: Combinatorics, Probability and Computing (2002)

We show that the limiting distribution of the number of comparisons used by Hoare's quickselect algorithm when given a random permutation of n elements for finding the mth-smallest element, where m = o(n), is the Dickman function. The limiting distribution of the number of exchanges is also derived.
Developing Secure Networked Web-Based Systems Using Model-based Risk Assessment and UMLsec
Authors: Siv Hilde Houmb, Jan Jürjens
Venue: Proceedings of the Tenth Asia-Pacific Software Engineering Conference Software Engineering Conference (2003)

Despite a growing awareness of security issues in networkedcomputing systems, most development processesused today still do not take security aspects into account.To address this problem, we designed a process for developingsecure networked systems based on the extension of theUnified Modeling Language (UML) for secure systems developmentUMLsec and on the concept of model-based riskassessment (MBRA). Enterprise information such as securitypolicies, business goals, policies and processes are supportedthrough activities in the model-based integrated developmentprocess. These are then refined to security requirementsat a more technical level, which can be expressedusing UMLsec, and which can be analysed mechanicallyusing the tool-support for UMLsec.
An efficient 3D grid based scheduling for heterogeneous systems
Authors: Anthony T. Chronopoulos, Daniel Grosu, Andrew M. Wissink, Manuel Benche, Jingyu Liu
Venue: Journal of Parallel and Distributed Computing (2003)

The cost/performance ratio of networks of workstations has been constantly improving. This trend is expected to continue in the near future. The aggregate peak rate of such systems often matches or exceeds the peak rate offered by the fastest parallel computers. This has motivated research toward using a network of computers, interconnected via a fast network (cluster system) or a simple Local Area Network (LAN) (distributed system), for high performance concurrent computations. Some of the important research issues arise such as (i) Problem partitioning and virtual interconnection topology mapping; (ii) Execution scheduling and load balancing.Past results exist for grid partitioning (into subdomains) and mapping to parallel and distributed systems. In our work we consider the problem of grid partitioning of a 3D domain arising in aircraft CFD simulations in order to schedule tasks for load balanced execution on a heterogeneous distributed system. This problem has additional restrictions on how to partition the grid. Past work for this problem were on parallel systems with only few processor configurations. We derive heuristic algorithms for: (1) homogeneous systems with any number of processors; (2) heterogeneous systems taking into account the processor speed and memory capacity. We implement our algorithms on a dedicated network of workstations (using MPI) and test them with a CFD simulation code (TURNS--Transonic Unsteady Rotor Navier Stokes).
Modality control of an active camera for an object recognition task
Authors: Felipe Trujillo-Romero, Víctor Ayala-Ramírez, René Jaime-Rivas
Venue: Proceedings of the 14th International Conference on Electronics, Communications and Computers (2004)

In this paper, we show an active object recognition system. This system uses a mutual information frameworkin order to choose the optimal parameters of an activecamera for recognizing an unknown object. In a learningstep, our system builds a database of all objects by meansof a controlled acquisition process over a set of actions.These actions are taken from the set of different feasible configurations for our active sensor. Actions includepan, tilt and zoom values for an active camera. For everyaction, we compute the conditional probability density ofobserving some features of interest in the objects to recognize. Using a sequential decision making process, oursystem determines an optimal action that increase discrimination between objects in our database. This procedure iterate until a decision about the class of the unknown object can be done. We use the color patch meanover an interest region in our image as the discrimination feature. We have used a set 8 different soda bottles asour test objects and we have obtained a recognition rateof about 99%. The system needs to iterate about 4 times(that is, to perform 4 actions) before being capable of making a decision.
The Transfer of Experience in Groups of Organizations: Implications for Performance and Competition
Authors: Paul Ingram, Tal Simons
Venue: Management Science (2002)

Groups of organizations are pervasive, although there is little systematic knowledge about how they affect their members. We examine one dimension of the operation of organization groups, the transfer of experience. Our core argument is that organization groups may create benefits for their members, but problems for those outside the group. Within the group they can facilitate the transfer of experience among their members by creating mechanisms for communication, incentives for helping, and by promoting understanding. The predicted pattern of experience transfer should improve performance of those within the group, but also has implications for those outside it. Experience accumulated in one organization group strengthens the competitiveness of its organizations, and thereby harms competitors outside the group. Thus, organization groups are fundamental both for the functioning of their members and the competitive dynamics of their industries. Our longitudinal analysis of the profitability of kibbutz agriculture supports both these claims. Between 1954 and 1965 (the years of this study), almost all kibbutzim were part of organization groups. Kibbutzim became more profitable as a function of the experience of others in their group. Their profitability was reduced, however, as a function of experience of others outside their group.
Minimal Blocking Sets in PG(2, 8) and Maximal Partial Spreads in PG(3, 8)
Authors: J. Barát, A. Del Fra, S. Innamorati, L. Storme
Venue: Designs, Codes and Cryptography (2004)

We prove that PG(2, 8) does not contain minimal blocking sets of size 14. Using this result we prove that 58 is the largest size for a maximal partial spread of PG(3, 8). This supports the conjecture that q2&minus;q+ 2 is the largest size for a maximal partial spread of PG(3, q), q>7.