Results 1 - 10 of 118,077

How much should we trust differences-in-differences estimates?

by Marianne Bertrand, Esther Duflo, Sendhil Mullainathan , 2003
"... Most papers that employ Differences-in-Differences estimation (DD) use many years of data and focus on serially correlated outcomes but ignore that the resulting standard errors are inconsistent. To illustrate the severity of this issue, we randomly generate placebo laws in state-level data on femal ..."
Abstract - Cited by 828 (1 self) - Add to MetaCart
Most papers that employ Differences-in-Differences estimation (DD) use many years of data and focus on serially correlated outcomes but ignore that the resulting standard errors are inconsistent. To illustrate the severity of this issue, we randomly generate placebo laws in state-level data

Ptolemy: A Framework for Simulating and Prototyping Heterogeneous Systems

by Joseph Buck, Soonhoi Ha, Edward A. Lee, David G. Messerschmitt , 1992
"... Ptolemy is an environment for simulation and prototyping of heterogeneous systems. It uses modern object-oriented software technology (C++) to model each subsystem in a natural and efficient manner, and to integrate these subsystems into a whole. Ptolemy encompasses practically all aspects of design ..."
Abstract - Cited by 571 (89 self) - Add to MetaCart
of designing signal processing and communications systems, ranging from algorithms and communication strategies, simulation, hardware and software design, parallel computing, and generating real-time prototypes. To accommodate this breadth, Ptolemy must support a plethora of widely-differing design styles

Valuing American options by simulation: A simple least-squares approach

by Francis A. Longstaff, Eduardo S. Schwartz - Review of Financial Studies , 2001
"... This article presents a simple yet powerful new approach for approximating the value of America11 options by simulation. The kcy to this approach is the use of least squares to estimate the conditional expected payoff to the optionholder from continuation. This makes this approach readily applicable ..."
Abstract - Cited by 517 (9 self) - Add to MetaCart
This article presents a simple yet powerful new approach for approximating the value of America11 options by simulation. The kcy to this approach is the use of least squares to estimate the conditional expected payoff to the optionholder from continuation. This makes this approach readily

A modular three-dimensional finite-difference ground-water flow model

by Model (michael Mcdonald, Arlen Harbaugh - U.S. Geological Survey Techniques of WaterResources Investigations Book 6, Chapter A1 , 1988
"... The primary objective of this course is to discuss the principals of finite difference methods and their applications in groundwater modeling. The emphasis of the class lectures is on the theoretical aspects of numerical modeling (finite difference method). Steps involved in simulation of groundwate ..."
Abstract - Cited by 508 (5 self) - Add to MetaCart
The primary objective of this course is to discuss the principals of finite difference methods and their applications in groundwater modeling. The emphasis of the class lectures is on the theoretical aspects of numerical modeling (finite difference method). Steps involved in simulation

Volume of Fluid (VOF) Method for the Dynamics of Free Boundaries

by C. W. Hirt, B. D. Nichols , 1981
"... Several methods have been previously used to approximate free boundaries in finite difference numerical simulations. A simple, but powerful, method is described that is based on the concept of a fractional volume of fluid (VOF). This method is shown to be more flexible and efficient than other metho ..."
Abstract - Cited by 603 (3 self) - Add to MetaCart
Several methods have been previously used to approximate free boundaries in finite difference numerical simulations. A simple, but powerful, method is described that is based on the concept of a fractional volume of fluid (VOF). This method is shown to be more flexible and efficient than other

ASCENT: Adaptive self-configuring sensor networks topologies

by Alberto Cerpa, Deborah Estrin , 2004
"... Advances in microsensor and radio technology will enable small but smart sensors to be deployed for a wide range of environmental monitoring applications. The low per-node cost will allow these wireless networks of sensors and actuators to be densely distributed. The nodes in these dense networks w ..."
Abstract - Cited by 449 (15 self) - Add to MetaCart
configuration, and the environmental dynamics will preclude design-time preconfiguration. Therefore, nodes will have to self-configure to establish a topology that provides communication under stringent energy constraints. ASCENT builds on the notion that, as density increases, only a subset of the nodes

An Integrated Experimental Environment for Distributed Systems and Networks

by Brian White, Jay Lepreau, Leigh Stoller, Robert Ricci, Shashi Guruprasad, Mac Newbold, Mike Hibler, Chad Barb, Abhijeet Joglekar - In Proc. of the Fifth Symposium on Operating Systems Design and Implementation , 2002
"... Three experimental environments traditionally support network and distributed systems research: network emulators, network simulators, and live networks. The continued use of multiple approaches highlights both the value and inadequacy of each. Netbed, a descendant of Emulab, provides an experimenta ..."
Abstract - Cited by 688 (41 self) - Add to MetaCart
an experimentation facility that integrates these approaches, allowing researchers to configure and access networks composed of emulated, simulated, and wide-area nodes and links. Netbed's primary goals are ease of use, control, and realism, achieved through consistent use of virtualization and abstraction.

The Player/Stage Project: Tools for Multi-Robot and Distributed Sensor Systems

by Brian P. Gerkey, Richard T. Vaughan, Andrew Howard - In Proceedings of the 11th International Conference on Advanced Robotics , 2003
"... This paper describes the Player/Stage software tools applied to multi-robot, distributed-robot and sensor network systems. Player is a robot device server that provides network transparent robot control. Player seeks to constrain controller design as little as possible; it is device independent, non ..."
Abstract - Cited by 622 (14 self) - Add to MetaCart
, non-locking and language- and style-neutral. Stage is a lightweight, highly configurable robot simulator that supports large populations. Player/Stage is a community Free Software project. Current usage of Player and Stage is reviewed, and some interesting research opportunities opened up

Geography-informed Energy Conservation for Ad Hoc Routing

by Ya Xu, John Heidemann, Deborah Estrin - ACM MOBICOM , 2001
"... We introduce a geographical adaptive fidelity (GAF) algorithm that reduces energy consumption in ad hoc wireless networks. GAF conserves energy by identifying nodes that are equivalent from a routing perspective and then turning off unnecessary nodes, keeping a constant level of routing fidelity. GA ..."
Abstract - Cited by 1045 (21 self) - Add to MetaCart
. GAF moderates this policy using application- and system-level information; nodes that source or sink data remain on and intermediate nodes monitor and balance energy use. GAF is independent of the underlying ad hoc routing protocol; we simulate GAF over unmodified AODV and DSR. Analysis and simulation

Evolutionary Computing

by A. E. Eiben , M. Schoenauer , 2005
"... Evolutionary computing (EC) is an exciting development in Computer Science. It amounts to building, applying and studying algorithms based on the Darwinian principles of natural selection. In this paper we briefly introduce the main concepts behind evolutionary computing. We present the main compone ..."
Abstract - Cited by 624 (35 self) - Add to MetaCart
components all evolutionary algorithms (EA), sketch the differences between different types of EAs and survey application areas ranging from optimization, modeling and simulation to entertainment.
Results 1 - 10 of 118,077