ppxscal/embedding_network huggingface dataset:
Cross-Disciplinary Evidence for Hyperbolic Social Discount Rates
Authors: Norman Henderson, Ian Langford
Venue: Management Science (1998)

Researchers in different disciplines have independently found evidence to suggest that the social discount rate may be hyperbolic, rather than exponential, in nature. Both behaviorist research and some empirical economics studies support the hyperbolic discounting hypothesis. U.S. and U.K. government discounting dispensations for some long-run public development projects are explicable in terms of an underlying hyperbolic social discount rate. A statistical aggregation argument demonstrates that even if the behaviorist, economics and public choice evidence for hyperbolic discounting is not conclusive, the social discount rate of a set of people who individually express time preferences best modeled by exponential discounting functions is nonetheless hyperbolic. Further empirical economics studies of discounting preferences are required. Comparisons of different national discounting practices would also be useful to see how widespread is the use of unusually low exponential rates of discount for long-run projects. The application of hyperbolic discounting would have most impact in long-run benefit-cost analyses. However, government agencies would require overwhelming evidence before switching from exponential to hyperbolic discounting.
Noise analysis of non-autonomous radio frequency circuits
Authors: Amit Mehrotra, Alberto L. Sangiovanni-Vincentelli
Venue: Proceedings of the 1999 IEEE/ACM international conference on Computer-aided design (1999)

In this paper we consider the important problem of noise analysis of non-autonomous nonlinear RF circuits in presence of input signal phase noise. We formulate this problem as a stochastic differential equation and solve it in the presence of circuit white noise sources. We show that the output noise of a nonlinear non-autonomous circuit, driven by a periodic input signal with phase noise, is stationary and not cyclostationary (as would be predicted by traditional analyses). We also show that effect of input signal phase noise is to act as additional white noise source. This result is derived using a full nonlinear analysis of the problem and cannot be predicted by traditional linear analysis based techniques. Input signal phase noise can be an important portion of the overall output noise of the non-autonomous circuit. In our opinion, existing analyses have not considered this effect in a rigorous manner. We also relate this solution to results of the existing nonlinear time domain and frequency domain methods of noise analysis and point out the modifications required for the present techniques. We illustrate our technique using an example.
Structural Results About On-line Learning Models With and Without Queries
Authors: Peter Auer, Philip M. Long
Venue: Machine Learning (1999)

We solve an open problem of Maass and Tur&aacute;n, showing that the optimal mistake-bound when learning a given concept class without membership queries is within a constant factor of the optimal number of mistakes plus membership queries required by an algorithm that can ask membership queries. Previously known results imply that the constant factor in our bound is best possible.We then show that, in a natural generalization of the mistake-bound model, the usefulness to the learner of arbitrary &ldquo;yes-no&rdquo; questions between trials is very limited. We show that several natural structural questions about relatives of the mistake-bound model can be answered through the application of this general result. Most of these results can be interpreted as saying that learning in apparently less powerful (and more realistic) models is not much more difficult than learning in more powerful models.
A Feasible Directions Algorithm for Optimal Control Problems with State and Control Constraints: Convergence Analysis
Authors: R. Pytlak, R. B. Vinter
Venue: SIAM Journal on Control and Optimization (1998)

In this paper we describe an optimization algorithm for the computation of solutions to optimal control problems with control, state, and terminal constraints. Inequality and equality constraints are dealt with by means of feasible directions and exact penalty approaches, respectively. We establish a general convergence property of the algorithm which makes no reference to the existence of accumulation points; in this analysis the compactness of the space of relaxed controls is used only to guarantee boundedness of the sequence of penalty parameters. We also demonstrate that relaxed accumulation points of sequences generated by the algorithm satisfy standard first-order necessary conditions of optimality. The algorithm contains a number of computation saving features, including an $\varepsilon$-active strategy for dealing with the "infinite dimensional" inequality constraints. Our convergence analysis provides techniques for studying the convergence properties of related optimization algorithms in which direction-finding subproblems involve the approximation of directional derivatives of the Chebyshev functional associated with state constraints. A companion paper provides details of implementation and numerical examples.
On the Lagrange--Newton--SQP Method for the Optimal Control of Semilinear Parabolic Equations
Authors: Fredi Tröltzsch
Venue: SIAM Journal on Control and Optimization (1999)

A class of Lagrange--Newton--SQP methods is investigated for optimal control problems governed by semilinear parabolic initial-boundary value problems. Distributed and boundary controls are given, restricted by pointwise upper and lower bounds. The convergence of the method is discussed in appropriate Banach spaces. Based on a weak second order sufficient optimality condition for the reference solution, local quadratic convergence is proved. The proof is based on the theory of Newton methods for generalized equations in Banach spaces.
Power Additivity and Orthogonality
Authors: Robert E. Hartwig, Peter Semrl
Venue: SIAM Journal on Matrix Analysis and Applications (1999)

The relation between rank additivity and orthogonality is analyzed. The central role played by Cochran's theorem is illustrated and the properties of orthogonal and power-additive families are investigated.
Perl in a nutshell: a desktop quick reference
Authors: Ellen Siever, Stephen Spainhour, Nathan Patwardham
Venue:  (1999)

The perfect companion for working programmers, Perl in a Nutshell is a comprehensive reference guide to the world of Perl. It contains everything you need to know for all but the most obscure Perl questions. This wealth of information is packed into an efficient, extraordinarily usable format.
Towards true crosstalk noise analysis
Authors: Pinhong Chen, Kurt Keutzer
Venue: Proceedings of the 1999 IEEE/ACM international conference on Computer-aided design (1999)

Accurate noise analysis is currently of significant concern to high-performance designs, and the number of signals susceptible to noise effects will certainly increase in smaller process geometries. Our approach uses a combination of temporal and functional information to eliminate false transition combinations and thereby overcome insufficiencies in static noise analysis. A similar idea arises in timing analysis where functional and timing information is used to eliminate false paths. The goal of our work is to develop an algorithm, software tool, and noise analysis flow that provide an accurate and conservative approach to noise analysis. In particular, this paper proposes an approach to identifying a pair of vectors that exercises the maximum crosstalk noise.
Compatability and interaction style in computer graphics
Authors: George W. Fitzmaurice, Bill Buxton
Venue: ACM SIGGRAPH Computer Graphics (1998)

Recent trends in human computer interaction have focused on representations based on physical reality [4, 5, 6, 8]. The idea is to provide richer, more intuitive handles for control and manipulation compared to traditional graphical user interfaces (GUIs) using a mouse. This trend underscores the need to examine the concept of manipulation and to further understand what we want to manipulate versus what we can easily manipulate. Implicit in this is the notion that the bias of the UI is often incompatible with user needs.The main goal of UI design is to reduce complexity while augmenting the ability of users to get their work done. A fundamental belief underlying our research is that complexity lies not only in what is purchased from the software and hardware manufacturers, but also in what the user creates with it. It is not just a question of making buttons and menus easier to learn and more efficient to use. It is also a question of "Given that I've created this surface in this way, how can it now be modified to achieve my current design objective?" (The observation is that how the user created the surface in the first place will affect the answer to the question.) Our thesis is that appropriate design of the system can minimize both kinds of complexity: that inherent in accessing the functionality provided by the vendor, and that created by the user. The literature focuses on the former. In what follows, we investigate some of the issues in achieving the latter. In so doing, we structure our discussion around questions of compatibility.
PingPongPlus: design of an athletic-tangible interface for computer-supported cooperative play
Authors: Hiroshi Ishii, Craig Wisneski, Julian Orbanes, Ben Chun, Joe Paradiso
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: the CHI is the limit (1999)

This paper introduces a novel interface for digitally-augmented cooperative play. We present the concept of the athletic-tangible interface, a new class of interaction which uses tangible objects and full-body motion in physical spaces with digital augmentation. We detail the implementation of PingPongPlus, a reactive ping-pong table, which features a novel sound-based ball tracking technology. The game is augmented and transformed with dynamic graphics and sound, determined by the position of impact, and the rhythm and style of play. A variety of different modes of play and initial experiences with PingPongPlus are also described.
Synchronization in portable device drivers
Authors: Stein J. Ryan
Venue: ACM SIGOPS Operating Systems Review (1998)

We present an overview of the synchronization mechanisms offered to device drivers by different operating systems and develop a foundation for writing portable device drivers by unifying these mechanisms. Our foundation has been used to implement an efficient portable cluster adapter driver for three different operating systems as part of the runtime system for a heterogeneous PC cluster. We show how our portable synchronization mechanisms map to the native synchronization mechanisms of these three operating systems.
Trust Region Algorithms and Timestep Selection
Authors: Desmond J. Higham
Venue: SIAM Journal on Numerical Analysis (1999)

Unconstrained optimization problems are closely related to systems of ordinary differential equations (ODEs) with gradient structure. In this work, we prove results that apply to both areas. We analyze the convergence properties of a trust region, or Levenberg--Marquardt, algorithm for optimization. The algorithm may also be regarded as a linearized implicit Euler method with adaptive timestep for gradient ODEs. From the optimization viewpoint, the algorithm is driven directly by the Levenberg--Marquardt parameter rather than the trust region radius. This approach is discussed, for example, in [R. Fletcher, Practical Methods of Optimization, 2nd ed., John Wiley, New York, 1987], but no convergence theory is developed. We give a rigorous error analysis for the algorithm, establishing global convergence and an unusual, extremely rapid, type of superlinear convergence. The precise form of superlinear convergence is exhibited---the ratio of successive displacements from the limit point is bounded above and below by geometrically decreasing sequences. We also show how an inexpensive change to the algorithm leads to quadratic convergence. From the ODE viewpoint, this work contributes to the theory of gradient stability by presenting an algorithm that reproduces the correct global dynamics and gives very rapid local convergence to a stable steady state.
The Efficiency of Ballstep Subgradient Level Methods for Convex Optimization
Authors: Krzysztof C. Kiwiel, Torbjorn Larsson, P. O. Lindberg
Venue: Mathematics of Operations Research (1999)

We study subgradient methods for convex optimization that use projections onto successive approximations of level sets of the objective corresponding to estimates of the optimal value. We establish convergence and efficiency estimates for simple ballstep level controls without requiring that the feasible set be compact. Our framework may handle accelerations based on "cheap" projections, surrogate constraints, and conjugate subgradient techniques.
Diffusive load balancing schemes on heterogeneous networks
Authors: Robert Elsässer, Burkhard Monien, Robert Preis
Venue: Proceedings of the twelfth annual ACM symposium on Parallel algorithms and architectures (2000)

Up to now, diffusive load balancing schemes have only been developed for homogeneous networks. We generalize existing diffusion schemes, in order to deal with heterogeneous networks. In these networks, every processor can have arbitrary computing power, and the load has to be balanced proportionally to these weights. The balancing flow that is calculated by the schemes for homogeneous networks is minimal with regard to the l2-norm and we prove this to hold true for the generalized schemes, too. By means of a number of experiments we demonstrate the usability of the generalized schemes on heterogeneous networks.
SWEETPEA: software tools for programmable embodied agents
Authors: Michael Kaminsky, Paul Dourish, W. Keith Edwards, Anthony LaMarca, Michael Salisbury, Ian Smith
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems: the CHI is the limit (1999)

Programmable Embodied Agents are portable, wireless, interactive devices embodying specific, differentiable, interactive characteristics. They take the form of identifiable characters who reside in the physical world and interact directly with users. They can act as an out-of-band communication channel between users, as proxies for system components or other users, or in a variety of other roles. Traditionally, research into such devices has been based on costly custom hardware. In this paper, we report on our explorations of the space of physical character-based interfaces built on recently available stock consumer hardware platforms, structured around an initial framework of applications.
The impact of job arrival patterns on parallel scheduling
Authors: Mark S. Squillante, David D. Yao, Li Zhang
Venue: ACM SIGMETRICS Performance Evaluation Review (1999)

In this paper we present an initial analysis of the job arrival patterns from a real parallel computing system and we develop a class of traffic models to characterize these arrival patterns. Our analysis of the job arrival data illustrates traffic patterns that exhibit heavy-tail behavior and other characteristics which are quite different from the arrival processes used in previous studies of parallel scheduling. We then investigate the impact of these arrival traffic patterns on the performance of parallel space-sharing scheduling strategies.
Electronic market: the roadmap for university libraries and members to survive in the information jungle
Authors: Michael Christoffel, Sebastian Pulkowski, Bethina Schmitt, Peter C. Lockemann
Venue: ACM SIGMOD Record (1998)

This contribution argues that electronic markets can serve as a powerful mechanism to entice providers to identify their customer base and to offer customer-oriented, high-quality and economical services and to induce customers to a more focused and price-conscious behavior. The paper claims that this should be particularly true for the provision and access to scientific literature where the tradition so far has been mostly free access by customers and non-transparent cost accounting and service procurement by university libraries. We report on a project for developing a technical network infrastructure that allows for a more cost-transparent access to scientific literature by campus users and attempts to add a competitive element to library services. Equally important, it provides added value to the users so that they can orient themselves in the vast expanses of scientific literature much faster and more economically. We cover three major elements of the infrastructure: user agents, traders and source wrappers.
Exact Penalization of Mathematical Programs with Equilibrium Constraints
Authors: Stefan Scholtes, Michael Stöhr
Venue: SIAM Journal on Control and Optimization (1999)

We study theoretical and computational aspects of an exact penalization approach to mathematical programs with equilibrium constraints (MPECs). In the first part, we prove that a Mangasarian--Fromovitz-type condition ensures the existence of a stable local error bound at the root of a real-valued nonnegative piecewise smooth function. A specification to nonsmooth formulations of equilibrium constraints, e.g., complementarity conditions or normal equations, provides conditions which guarantee the existence of a nonsmooth exact penalty function for MPECs. In the second part, we study a trust region minimization method for a class of composite nonsmooth functions which comprises exact penalty functions arising from MPECs. We prove a global convergence result for the general method and incorporate a penalty update rule. A further specification results in an SQP trust region method for MPECs based on an \(\ell_1\) penalty function.
A survey of software inspection checklists
Authors: Bill Brykczynski
Venue: ACM SIGSOFT Software Engineering Notes (1999)

Software inspection processes call for a checklist to provide reviewers with hints and recommendations for finding defects during the examination of a workproduct. Many checklists have been published since Michael Fagan created the inspection process in the mid-1970's. This paper surveys 117 checklists from 24 sources. Different categories of checklist items are discussed and examples are provided of good checklist items as well as those that should be avoided.
Convexity of the Joint Numerical Range
Authors: Chi-Kwong Li, Yiu-Tung Poon
Venue: SIAM Journal on Matrix Analysis and Applications (1999)

Let A=(A1, . . ., Am) be an m-tuple of n &times; n Hermitian matrices. For $1 \le k \le n$, the $k${\rm th} joint numerical range of A is defined by $$W_k(A) = \{ ({\rm \tr}(X^*A_1X), \dots, {\rm \tr}(X^*A_mX) ): X \in {\bf C}^{n\times k}, X^*X = I_k \}.$$ We consider linearly independent families of Hermitian matrices {A1, . . . , Am} so that Wk(A) is convex. It is shown that m can reach the upper bound 2k(n-k)+1. A key idea in our study is relating the convexity of Wk(A) to the problem of constructing rank k orthogonal projections under linear constraints determined by A. The techniques are extended to study the convexity of other generalized numerical ranges and the corresponding matrix construction problems.
An Introduction to Variational Methods for Graphical Models
Authors: Michael I. Jordan, Zoubin Ghahramani, Tommi S. Jaakkola, Lawrence K. Saul
Venue: Machine Learning (1999)

This paper presents a tutorial introduction to the use of variational methods for inference and learning in graphical models (Bayesian networks and Markov random fields). We present a number of examples of graphical models, including the QMR-DT database, the sigmoid belief network, the Boltzmann machine, and several variants of hidden Markov models, in which it is infeasible to run exact inference algorithms. We then introduce variational methods, which exploit laws of large numbers to transform the original graphical model into a simplified graphical model in which inference is efficient. Inference in the simpified model provides bounds on probabilities of interest in the original model. We describe a general framework for generating variational transformations based on convex duality. Finally we return to the examples and demonstrate how variational algorithms can be formulated in each case.
On Deriving the Quasi-Minimal Residual Method
Authors: M. Sauren, H. M. Bücker
Venue: SIAM Review (1998)

A new derivation of the quasi-minimal residual (QMR) method for the solution of a system of linear equations is presented. This derivation differs from the original one in solving a particular least-squares problem by applying simple recurrences rather than computing a QR decomposition by means of Givens rotations.
Measuring disagreement in groups facing limited-choice problems
Authors: Brian Whitworth, Roy Felton
Venue: ACM SIGMIS Database (1999)

Agreement is an important concept in group interaction, both for computer-mediated and face-to-face groups. This paper presents a measure of disagreement, D, for groups facing limited-choice problems, based on the average pair-wise separations between group member responses. It allows a meaningful disagreement value to be assigned to any group response pattern. The same logic also provides an individual level measure, d, giving the disagreement of individuals within the group.The properties of this measure are explored and found to be similar to those expected of a measure of disagreement. For nominal data, such as produced by questionnaire responses, D offers a standard scale of disagreement from 0 to 1 for any size group facing any number of mutually exclusive choices. The measures can be inverted to show agreement, although this does not necessarily predict group coalescence, as polarized groups can also contain considerable agreement.The measure can be extended to ranked, interval, and ratio-scale solution choices. In this case, D is equal to twice the variance of the solution scores. The existence of an equivalent measure of ecological diversity further suggests the possibility of a generalized concept of dispersion. An example application is given, illustrating how disagreement at both the individual and group levels can be meaningfully and usefully represented by d and D.
Determinant: Old Algorithms, New Insights
Authors: Meena Mahajan, V. Vinay
Venue: SIAM Journal on Discrete Mathematics (1999)

In this paper we approach the problem of computing the characteristic polynomial of a matrix from the combinatorial viewpoint. We present several combinatorial characterizations of the coefficients of the characteristic polynomial in terms of walks and closed walks of different kinds in the underlying graph. We develop algorithms based on these characterizations and show that they tally with well-known algorithms arrived at independently from considerations in linear algebra.
Plane Partitions and Characters of the Symmetric Group
Authors: Ernesto Vallejo
Venue: Journal of Algebraic Combinatorics: An International Journal (2000)

In this paper we show that the existence of plane partitions, which are minimal in a sense to be defined, yields minimal irreducible summands in the Kronecker product &chi;^&lambda; &otimes; &chi;^&mu; of two irreducible characters of the symmetric group S(n). The minimality of the summands refers to the dominance order of partitions of n. The multiplicity of a minimal summand &chi;^&nu; equals the number of pairs of Littlewood-Richardson multitableaux of shape (&lambda;, &mu;), conjugate content and type &nu;. We also give lower and upper bounds for these numbers.