The Computational Structure of Monotone Monadic SNP and Constraint Satisfaction: A Study through Datalog and Group Theory

This paper isolates a class (of problems specified by) "monotone monadic SNP without inequality" which may exhibit a dichotomy, and explains the placing of all these restrictions by showing, essentially using Ladner's theorem, that classes obtained by using only two of the above three restrictions do not show this dichotomy. Expand The benefits of relaxing punctuality

A temporal language is introduced that can constrain the time difference between events only with finite (yet arbitrary) precision and show the resulting logic to be EXPACE-complete, allowing the authors to develop an algorithm for the verification of timing properties of real time systems with a dense semantics. Expand The Benefits of Relaxing Punctuality

This work introduces a temporal language that can constrain the time difference between events only with finite, yet arbitrary, precision and show the resulting logic to be EXPSPACE-complete. Expand Optimal algorithms for approximate clustering

This work gives a polynomial time approximation scheme that estimates the optimal number of clusters under the second measure of cluster size within factors arbitrarily close to 1 for a fixed cluster size. Expand Achieving anonymity via clustering

This is the first set of algorithms for the anonymization problem where the performance is independent of the anonymity parameter k, and extends the algorithms to allow an ε fraction of points to remain unclustered, i.e., deleted from the anonymized publication. Expand A New Fixed Point Approach for Stable Networks and Stable Marriages

- T. Feder
- Computer Science
- J. Comput. Syst. Sci.
- 1 October 1992

This approach builds on structural properties of these networks and exposes close ties with the theory of retracts and isometric embeddings for product graphs, which gives new efficient algorithms for questions of representation, enumeration, and optimization in stable matching. Expand List Homomorphisms to Reflexive Graphs

- T. Feder, P. Hell
- Mathematics, Computer Science
- J. Comb. Theory, Ser. B
- 1 March 1998

A polynomial time algorithm is given to solve the problem when the input graph is an interval graph and it is argued that the complexity of certain other modifications of the problem are likely to be difficult to classify. Expand Clique partitions, graph compression and speeding-up algorithms

The notion of a compression of a graph ~ is defined and used to efficiently compute an optimal compression for graphs of a given size to improve upon the running times of the best-known algorithms for these problems. Expand