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181
Similarity Flooding: A Versatile Graph Matching Algorithm and Its Application to Schema Matching
, 2002
"... Matching elements of two data schemas or two data instances plays a key role in data warehousing, ebusiness, or even biochemical applications. In this paper we present a matching algorithm based on a fixpoint computation that is usable across different scenarios. The algorithm takes two graphs (sch ..."
Abstract

Cited by 436 (11 self)
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Matching elements of two data schemas or two data instances plays a key role in data warehousing, ebusiness, or even biochemical applications. In this paper we present a matching algorithm based on a fixpoint computation that is usable across different scenarios. The algorithm takes two graphs (schemas, catalogs, or other data structures) as input, and produces as output a mapping between corresponding nodes of the graphs. Depending on the matching goal, a subset of the mapping is chosen using filters. After our algorithm runs, we expect a human to check and if necessary adjust the results. As a matter of fact, we evaluate the ‘accuracy ’ of the algorithm by counting the number of needed adjustments. We conducted a user study, in which our accuracy metric was used to estimate the labor savings that the users could obtain by utilizing our algorithm to obtain an initial matching. Finally, we illustrate how our matching algorithm is deployed as one of several highlevel operators in an implemented testbed for managing information models and mappings.
Privacy Preserving Auctions and Mechanism Design
, 1999
"... We suggest an architecture for executing protocols for auctions and, more generally, mechanism design. Our goal is to preserve the privacy of the inputs of the participants (so that no nonessential information about them is divulged, even a posteriori) while maintaining communication and computation ..."
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Cited by 185 (12 self)
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We suggest an architecture for executing protocols for auctions and, more generally, mechanism design. Our goal is to preserve the privacy of the inputs of the participants (so that no nonessential information about them is divulged, even a posteriori) while maintaining communication and computational efficiency. We achieve this goal by adding another party  the auction issuer  that generates the programs for computing the auctions but does not take an active part in the protocol. The auction issuer is not a trusted party, but is assumed not to collude with the auctioneer. In the case of auctions, barring collusion between the auctioneer and the auction issuer, neither party gains any information about the bids, even after the auction is over. Moreover, bidders can verify that the auction was performed correctly. The protocols do not require any communication between the bidders and the auction issuer and the computational efficiency is very reasonable. This architecture can be used to implement any mechanism design where the important factor is the complexity of the decision procedure.
Scheduling Algorithms for Inputqueued Cell Switches
, 1995
"... The algorithms described in this thesis are designed to schedule cells in a very highspeed, parallel, inputqueued crossbar switch. We present several novel scheduling algorithms that we have devised, each aims to match the set of inputs of an inputqueued switch to the set of outputs more effici ..."
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Cited by 138 (4 self)
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The algorithms described in this thesis are designed to schedule cells in a very highspeed, parallel, inputqueued crossbar switch. We present several novel scheduling algorithms that we have devised, each aims to match the set of inputs of an inputqueued switch to the set of outputs more efficiently, fairly and quickly than existing techniques. In Chapter 2 we present the simplest and fastest of these algorithms: SLIP  a parallel algorithm that uses rotating priority ("roundrobin") arbitration. SLIP is simple: it is readily implemented in hardware and can operate at high speed. SLIP has high performance: for uniform i.i.d. Bernoulli arrivals, SLIP is stable for any admissible load, because the arbiters tend to desynchronize. We present analytical results to model this behavior. However, SLIP is not always stable and is not always monotonic: adding more traffic can actually make the algorithm operate more efficiently. We present an approximate analytical model of this behavior. SLIP prevents starvation: all contending inputs are eventually served. We present simulation results, indicating SLIP's performance. We argue that SLIP can be readily implemented for a 32x32 switch on a single chip. In Chapter 3 we present iSLIP, an iterative algorithm that improves upon SLIP by converging on a maximal size match. The performance of iSLIP improves with up to log 2 N iterations. We show that although it has a longer running time than SLIP, an iSLIP scheduler is little more complex to implement. In Chapter 4 we describe maximum or maximal weight matching algorithms based on the occupancy of queues, or waiting times of cells. These algorithms are stabl...
Forming Coalitions in the Face of Uncertain Rewards
 In Proc. of AAAI94
, 1994
"... When agents are in an environment where they can interact with each other, groups of agents may agree to work together for the benefit of all the members of the group. Finding these coalitions of agents and determining how the joint reward should be divided among them is a difficult problem. This pr ..."
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Cited by 54 (0 self)
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When agents are in an environment where they can interact with each other, groups of agents may agree to work together for the benefit of all the members of the group. Finding these coalitions of agents and determining how the joint reward should be divided among them is a difficult problem. This problem is aggravated when the agents have different estimates of the value that the coalition will obtain. A "two agent auction" mechanism is suggested to complement an existing coalition formation algorithm for solving this problem. 1. The Problem Given a set of agents with different abilities and different information, there may be many opportunities for cooperation among the agents that will benefit all. Even more likely is the chance that a coalition can form, a subset of the agents working together, benefiting each agent in the group perhaps at the expense of the community as a whole. An agent following the economic principle of rationality will attempt to form a coalition which will max...
Deferred Acceptance Algorithms: History, Theory, Practice, and Open Questions
 INTERNATIONAL JOURNAL OF GAME THEORY, SPECIAL ISSUE IN HONOR OF DAVID GALE'S 85 TH BIRTHDAY
, 2007
"... The deferred acceptance algorithm proposed by Gale and Shapley (1962) has had a profound influence on market design, both directly, by being adapted into practical matching mechanisms, and, indirectly, by raising new theoretical questions. Deferred acceptance algorithms are at the basis of a number ..."
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Cited by 46 (5 self)
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The deferred acceptance algorithm proposed by Gale and Shapley (1962) has had a profound influence on market design, both directly, by being adapted into practical matching mechanisms, and, indirectly, by raising new theoretical questions. Deferred acceptance algorithms are at the basis of a number of labor market clearinghouses around the world, and have recently been implemented in school choice systems in Boston and New York City. In addition, the study of markets that have failed in ways that can be fixed with centralized mechanisms has led to a deeper understanding of some of the tasks a marketplace needs to accomplish to perform well. In particular, marketplaces work well when they provide thickness to the market, help it deal with the congestion that thickness can bring, and make it safe for participants to act effectively on their preferences. Centralized clearinghouses organized around the deferred acceptance algorithm can have these properties, and this has sometimes allowed failed markets to be reorganized.
RelationshipBased Clustering and Visualization for HighDimensional Data Mining
 INFORMS Journal on Computing
, 2002
"... In several reallife datamining... This paper proposes a relationshipbased approach that alleviates both problems, sidestepping the "curseofdimensionality" issue by working in a suitable similarity space instead of the original highdimensional attribute space. This intermediary similarity spac ..."
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Cited by 40 (10 self)
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In several reallife datamining... This paper proposes a relationshipbased approach that alleviates both problems, sidestepping the "curseofdimensionality" issue by working in a suitable similarity space instead of the original highdimensional attribute space. This intermediary similarity space can be suitably tailored to satisfy business criteria such as requiring customer clusters to represent comparable amounts of revenue. We apply efficient and scalable graphpartitioningbased clustering techniques in this space. The output from the clustering algorithm is used to reorder the data points so that the resulting permuted similarity matrix can be readily visualized in two dimensions, with clusters showing up as bands. While twodimensional visualization of a similarity matrix is by itself not novel, its combination with the ordersensitive partitioning of a graph that captures the relevant similarity measure between objects provides three powerful properties: (i) the highdimensionality of the data does not affect further processing once the similarity space is formed; (ii) it leads to clusters of (approximately) equal importance, and (iii) related clusters show up adjacent to one another, further facilitating the visualization of results. The visualization is very helpful for assessing and improving clustering. For example, actionable recommendations for splitting or merging of clusters can be easily derived, and it also guides the user toward the right number of clusters
Stable marriage with incomplete lists and ties
 In Proceedings of ICALP ’99: the 26th International Colloquium on Automata, Languages and Programming
, 1999
"... Abstract. The original stable marriage problem requires all men and women to submit a complete and strictly ordered preference list. This is obviously often unrealistic in practice, and several relaxations have been proposed, including the following two common ones: one is to allow an incomplete lis ..."
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Cited by 39 (13 self)
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Abstract. The original stable marriage problem requires all men and women to submit a complete and strictly ordered preference list. This is obviously often unrealistic in practice, and several relaxations have been proposed, including the following two common ones: one is to allow an incomplete list, i.e., a man is permitted to accept only a subset of the women and vice versa. The other is to allow a preference list including ties. Fortunately, it is known that both relaxed problems can still be solved in polynomial time. In this paper, we show that the situation changes substantially if we allow both relaxations (incomplete lists and ties) at the same time: the problem not only becomes NPhard, but also the optimal cost version has no approximation algorithm achieving the approximation ratio of N 1−ɛ, where N is the instance size, unless P=NP. 1
Greedy matchings
"... Suppose that each member of a set of n applicants ranks a subset of a set of m posts in strict order of preference. A matching is a set of (post, applicant) pairs such that each applicant and each post appears in at most one pair. A greedy matching is one in which the maximum possible number of appl ..."
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Cited by 33 (10 self)
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Suppose that each member of a set of n applicants ranks a subset of a set of m posts in strict order of preference. A matching is a set of (post, applicant) pairs such that each applicant and each post appears in at most one pair. A greedy matching is one in which the maximum possible number of applicants are matched to their rst choice post, and subject to that condition, the maximum possible number are matched to their second choice post, and so on. This is a relevant concept in any practical matching situation where the preferences are on only one side of the market. A greedy matching can be found by a transformation to the classical problem of maximum weight bipartite matching. However an exponentially decreasing sequence of weights must be assigned to the entries in each preference list, and this adversely a ects the complexity of the algorithm (and its performance in practice). Here, we describe a
GaleShapley Stable Marriage Problem Revisited: Strategic Issues and Applications
, 2000
"... . ..."
A FixedPoint Approach to Stable Matchings and Some Applications
, 2001
"... We describe a fixedpoint based approach to the theory of bipartite stable matchings. By this, we provide a common framework that links together seemingly distant results, like the stable marriage theorem of Gale and Shapley [11], the MenelsohnDulmage theorem [21], the KunduLawler theorem [19], Ta ..."
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Cited by 30 (5 self)
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We describe a fixedpoint based approach to the theory of bipartite stable matchings. By this, we provide a common framework that links together seemingly distant results, like the stable marriage theorem of Gale and Shapley [11], the MenelsohnDulmage theorem [21], the KunduLawler theorem [19], Tarski's fixed point theorem [32], the CantorBernstein theorem, Pym's linking theorem [22, 23] or the monochromatic path theorem of Sands et al. [29]. In this framework, we formulate a matroidgeneralization of the stable marriage theorem and study the lattice structure of generalized stable matchings. Based on the theory of lattice polyhedra and blocking polyhedra, we extend results of Vande Vate [33] and Rothblum [28] on the bipartite stable matching polytope.