Results 1 - 10 of 170,919

Measurement, Modeling, and Analysis of a Peer-to-Peer File-Sharing Workload

by Krishna P. Gummadi, Richard J. Dunn, Stefan Saroiu, Steven D. Gribble, Henry M. Levy, John Zahorjan , 2003
"... Peer-to-peer (P2P) file sharing accounts for an astonishing volume of current Internet tra#c. This paper probes deeply into modern P2P file sharing systems and the forces that drive them. By doing so, we seek to increase our understanding of P2P file sharing workloads and their implications for futu ..."
Abstract - Cited by 487 (7 self) - Add to MetaCart
for future multimedia workloads. Our research uses a three-tiered approach. First, we analyze a 200-day trace of over 20 terabytes of Kazaa P2P tra#c collected at the University of Washington. Second, we develop a model of multimedia workloads that lets us isolate, vary, and explore the impact of key system

The Web as a graph: measurements, models, and methods

by Jon M. Kleinberg, Ravi Kumar, Prabhakar Raghavan, Sridhar Rajagopalan, Andrew S. Tomkins , 1999
"... . The pages and hyperlinks of the World-Wide Web may be viewed as nodes and edges in a directed graph. This graph is a fascinating object of study: it has several hundred million nodes today, over a billion links, and appears to grow exponentially with time. There are many reasons --- mathematical, ..."
Abstract - Cited by 373 (11 self) - Add to MetaCart
, sociological, and commercial --- for studying the evolution of this graph. In this paper we begin by describing two algorithms that operate on the Web graph, addressing problems from Web search and automatic community discovery. We then report a number of measurements and properties of this graph

Measuring and testing the impact of news on volatility

by Robert F. Engle, Victor K. Ng , 1991
"... This paper introduces the News Impact Curve to measure how new information is incorporated into volatility estimates. A variety of new and existing ARCH models are compared and estimated with daily Japanese stock return data to determine the shape of the News Impact Curve. New diagnostic tests are p ..."
Abstract - Cited by 726 (14 self) - Add to MetaCart
This paper introduces the News Impact Curve to measure how new information is incorporated into volatility estimates. A variety of new and existing ARCH models are compared and estimated with daily Japanese stock return data to determine the shape of the News Impact Curve. New diagnostic tests

Structural equation modeling in practice: a review and recommended two-step approach.

by James C Anderson , J L Kellogg , David W Gerbing , Jeanne Brett , Claes Fornell , David Larcker , William Perreault Jr , James Steiger - Psychological Bulletin, , 1988
"... In this article, we provide guidance for substantive researchers on the use of structural equation modeling in practice for theory testing and development. We present a comprehensive, two-step modeling approach that employs a series of nested models and sequential chi-square difference tests. We di ..."
Abstract - Cited by 1825 (3 self) - Add to MetaCart
discuss the comparative advantages of this approach over a one-step approach. Considerations in specification, assessment of fit, and respecification of measurement models using confirmatory factor analysis are reviewed. As background to the two-step approach, the distinction between exploratory

Bayesian measures of model complexity and fit

by David J. Spiegelhalter, Nicola G. Best, Bradley P. Carlin - Journal of the Royal Statistical Society, Series B , 2002
"... [Read before The Royal Statistical Society at a meeting organized by the Research ..."
Abstract - Cited by 466 (4 self) - Add to MetaCart
[Read before The Royal Statistical Society at a meeting organized by the Research

Modeling and Forecasting Realized Volatility

by Torben G. Andersen, Tim Bollerslev, Francis X. Diebold, Paul Labys , 2002
"... this paper is built. First, although raw returns are clearly leptokurtic, returns standardized by realized volatilities are approximately Gaussian. Second, although the distributions of realized volatilities are clearly right-skewed, the distributions of the logarithms of realized volatilities are a ..."
Abstract - Cited by 549 (50 self) - Add to MetaCart
: a fractionally-integrated Gaussian vector autoregression (VAR) . Importantly, our approach explicitly permits measurement errors in the realized volatilities. Comparing the resulting volatility forecasts to those obtained from currently popular daily volatility models and more complicated high

Modeling TCP Throughput: A Simple Model and its Empirical Validation

by Jitendra Padhye, Victor Firoiu, Don Towsley, Jim Kurose , 1998
"... In this paper we develop a simple analytic characterization of the steady state throughput, as a function of loss rate and round trip time for a bulk transfer TCP flow, i.e., a flow with an unlimited amount of data to send. Unlike the models in [6, 7, 10], our model captures not only the behavior of ..."
Abstract - Cited by 1337 (36 self) - Add to MetaCart
of TCP’s fast retransmit mechanism (which is also considered in [6, 7, 10]) but also the effect of TCP’s timeout mechanism on throughput. Our measurements suggest that this latter behavior is important from a modeling perspective, as almost all of our TCP traces contained more timeout events than fast

Social force model for pedestrian dynamics

by Dirk Helbing, Péter Molnár - Physical Review E , 1995
"... It is suggested that the motion of pedestrians can be described as if they would be subject to ‘social forces’. These ‘forces ’ are not directly exerted by the pedestrians ’ personal environment, but they are a measure for the internal motivations of the individuals to perform certain actions (movem ..."
Abstract - Cited by 504 (25 self) - Add to MetaCart
It is suggested that the motion of pedestrians can be described as if they would be subject to ‘social forces’. These ‘forces ’ are not directly exerted by the pedestrians ’ personal environment, but they are a measure for the internal motivations of the individuals to perform certain actions

The Coordination of Arm Movements: An Experimentally Confirmed Mathematical Model

by Tamar Flash, Neville Hogans - Journal of neuroscience , 1985
"... This paper presents studies of the coordination of volun-tary human arm movements. A mathematical model is for-mulated which is shown to predict both the qualitative fea-tures and the quantitative details observed experimentally in planar, multijoint arm movements. Coordination is modeled mathematic ..."
Abstract - Cited by 688 (18 self) - Add to MetaCart
This paper presents studies of the coordination of volun-tary human arm movements. A mathematical model is for-mulated which is shown to predict both the qualitative fea-tures and the quantitative details observed experimentally in planar, multijoint arm movements. Coordination is modeled

An Empirical Study of Smoothing Techniques for Language Modeling

by Stanley F. Chen , 1998
"... We present an extensive empirical comparison of several smoothing techniques in the domain of language modeling, including those described by Jelinek and Mercer (1980), Katz (1987), and Church and Gale (1991). We investigate for the first time how factors such as training data size, corpus (e.g., Br ..."
Abstract - Cited by 1224 (21 self) - Add to MetaCart
We present an extensive empirical comparison of several smoothing techniques in the domain of language modeling, including those described by Jelinek and Mercer (1980), Katz (1987), and Church and Gale (1991). We investigate for the first time how factors such as training data size, corpus (e
Results 1 - 10 of 170,919