Learn More
ÐThe paper describes a new, logic-based methodology for analyzing observations. The key features of the Logical Analysis of Data (LAD) are the discovery of minimal sets of features necessary for explaining all observations and the detection of hidden patterns in the data capable of distinguishing observations describing ªpositiveº outcome events from(More)
We show that anyk-connected graphG = (V, E) has a sparsek-connected spanning subgraphG′ = (V, E′) with ¦E′¦ =O(k¦V¦) by presenting anO(¦E¦)-time algorithm to find one such subgraph, where connectivity stands for either edge-connectivity or node-connectivity. By using this algorithm as preprocessing, the time complexities of some graph problems related to(More)
Using the nested loops method, this paper addresses the problem of minimizing the number of page fetches necessary to evaluate a given query to a relational database. We first propose a data structure whereby the number of page fetches required for query evaluation is substantially reduced and then derive a formula for the expected number of page fetches.(More)
References [1] Leonidas Fegaras. A new heuristic for optimizing large queries. [2] Toshihide Ibaraki and Tiko Kameda. On the optimal nesting order for computing n-relational joins. Optimizing large join queries using a graph-based approach. [5] Guido Moerkotte and Thomas Neumann. Analysis of two existing and one new dynamic programming algorithm for the(More)
In this paper, we address a fundamental problem related to the induction of Boolean logic: Given a set of data, represented as a set of binary " true n-vectors " (or " positive examples ") and a set of " false n-vectors " (or " negative examples "), we establish a Boolean function (or an extension) f , so that f is true (resp., false) in every given true(More)
We provide constant ratio approximation algorithms for two NP-hard problems, the rectangle stabbing problem and the rectilinear partitioning problem. In the rectangle stabbing problem, we are given a set of rectangles in two-dimensional space, with the objective of stabbing all rectangles with the minimum number of lines parallel to the x and y axes. We(More)
The set covering problem (SCP) asks to choose a minimum cost family of subsets from given n subsets, which together covers the entire ground set. In this paper, we propose a local search algorithm for SCP, which have the following three features. (1) The use of 3-BLOCKINip neighborhood, which is the set of solutions obtainable from the current solution by(More)