Results 1 - 10 of 123,137

Proof verification and hardness of approximation problems

by Sanjeev Arora, Carsten Lund, Rajeev Motwani, Madhu Sudan, Mario Szegedy - IN PROC. 33RD ANN. IEEE SYMP. ON FOUND. OF COMP. SCI , 1992
"... We show that every language in NP has a probablistic verifier that checks membership proofs for it using logarithmic number of random bits and by examining a constant number of bits in the proof. If a string is in the language, then there exists a proof such that the verifier accepts with probabilit ..."
Abstract - Cited by 797 (39 self) - Add to MetaCart
vertex cover, maximum satisfiability, maximum cut, metric TSP, Steiner trees and shortest superstring. We also improve upon the clique hardness results of Feige, Goldwasser, Lovász, Safra and Szegedy [42], and Arora and Safra [6] and shows that there exists a positive ɛ such that approximating

Effects with Random Assignment: Results for Dartmouth Roommates

by Bruce Sacerdote , 2001
"... This paper uses a unique data set to measure peer effects among college roommates. Freshman year roommates and dormmates are randomly assigned at Dartmouth College. I find that peers have an impact on grade point average and on decisions to join social groups such as fraternities. Residential peer e ..."
Abstract - Cited by 554 (6 self) - Add to MetaCart
effects are markedly absent in other major life decisions such as choice of college major. Peer effects in GPA occur at the individual room level, whereas peer effects in fraternity membership occur both at the room level and the entire dorm level. Overall, the data provide strong evidence

Guaranteed minimumrank solutions of linear matrix equations via nuclear norm minimization,”

by Benjamin Recht , Maryam Fazel , Pablo A Parrilo - SIAM Review, , 2010
"... Abstract The affine rank minimization problem consists of finding a matrix of minimum rank that satisfies a given system of linear equality constraints. Such problems have appeared in the literature of a diverse set of fields including system identification and control, Euclidean embedding, and col ..."
Abstract - Cited by 562 (20 self) - Add to MetaCart
, and collaborative filtering. Although specific instances can often be solved with specialized algorithms, the general affine rank minimization problem is NP-hard, because it contains vector cardinality minimization as a special case. In this paper, we show that if a certain restricted isometry property holds

The Equity Premium: A Puzzle

by Rajnish Mehra, Edward C. Prescott - Journal of Monetary Economics , 1985
"... Restrictions that a class of general equilibrium models place upon the average returns of equity and Treasury bills are found to be strongly violated by the U.S. data in the 1889-1978 period. This result is robust to model specification and measurement problems. We conclude that, most likely, an equ ..."
Abstract - Cited by 1751 (40 self) - Add to MetaCart
Restrictions that a class of general equilibrium models place upon the average returns of equity and Treasury bills are found to be strongly violated by the U.S. data in the 1889-1978 period. This result is robust to model specification and measurement problems. We conclude that, most likely

An Empirical Characterization of the Dynamic Effects of changes in Government Spending and Taxes on Output

by Olivier Blanchard, Roberto Perotti - QUARTERLY JOURNAL OF ECONOMICS , 2002
"... This paper characterizes the dynamic effects of shocks in government spending and taxes on U. S. activity in the postwar period. It does so by using a mixed structural VAR/event study approach. Identification is achieved by using institutional information about the tax and transfer systems to identi ..."
Abstract - Cited by 664 (9 self) - Add to MetaCart
to identify the automatic response of taxes and spending to activity, and, by implication, to infer fiscal shocks. The results consistently show positive government spending shocks as having a positive effect on output, and positive tax shocks as having a negative effect. One result has a distinctly

Institutions Rule: The Primacy of Institutions over Geography and Integration in Economic Development

by Dani Rodrik, Arvind Subramanian, Francesco Trebbi - FREE UNIVERSITY OF BERLIN , 2004
"... We estimate the respective contributions of institutions, geography, and trade in determining income levels around the world, using recently developed instrumental variables for institutions and trade. Our results indicate that the quality of institutions “trumps” everything else. Once institutions ..."
Abstract - Cited by 817 (28 self) - Add to MetaCart
We estimate the respective contributions of institutions, geography, and trade in determining income levels around the world, using recently developed instrumental variables for institutions and trade. Our results indicate that the quality of institutions “trumps” everything else. Once institutions

A Threshold of ln n for Approximating Set Cover

by Uriel Feige - JOURNAL OF THE ACM , 1998
"... Given a collection F of subsets of S = f1; : : : ; ng, set cover is the problem of selecting as few as possible subsets from F such that their union covers S, and max k-cover is the problem of selecting k subsets from F such that their union has maximum cardinality. Both these problems are NP-har ..."
Abstract - Cited by 776 (5 self) - Add to MetaCart
o(1)) ln n), and previous results of Lund and Yannakakis, that showed hardness of approximation within a ratio of (log 2 n)=2 ' 0:72 lnn. For max k-cover we show an approximation threshold of (1 \Gamma 1=e) (up to low order terms), under the assumption that P != NP .

Object Detection with Discriminatively Trained Part Based Models

by Pedro F. Felzenszwalb, Ross B. Girshick, David McAllester, Deva Ramanan
"... We describe an object detection system based on mixtures of multiscale deformable part models. Our system is able to represent highly variable object classes and achieves state-of-the-art results in the PASCAL object detection challenges. While deformable part models have become quite popular, their ..."
Abstract - Cited by 1422 (49 self) - Add to MetaCart
We describe an object detection system based on mixtures of multiscale deformable part models. Our system is able to represent highly variable object classes and achieves state-of-the-art results in the PASCAL object detection challenges. While deformable part models have become quite popular

Interactive Graph Cuts for Optimal Boundary & Region Segmentation of Objects in N-D Images

by Yuri Y. Boykov , Marie-Pierre Jolly , 2001
"... In this paper we describe a new technique for general purpose interactive segmentation of N-dimensional images. The user marks certain pixels as “object” or “background” to provide hard constraints for segmentation. Additional soft constraints incorporate both boundary and region information. Graph ..."
Abstract - Cited by 1010 (20 self) - Add to MetaCart
In this paper we describe a new technique for general purpose interactive segmentation of N-dimensional images. The user marks certain pixels as “object” or “background” to provide hard constraints for segmentation. Additional soft constraints incorporate both boundary and region information. 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
) and Nelson's EGARCE. Similar results hold on a pre--crash sample period but are less strong.
Results 1 - 10 of 123,137