Beware greedy algorithms

Greedy Algorithms

Greedy Algorithms: Huffman Coding

Greedy Algorithms: In an optimization problem, we are given an input and asked to compute a structure, subject to various constraints, in a manner that either minimizes cost or maximizes profit. Such problems arise in many applications of science and engineering. Given an optimization problem, we are often faced with the question of whether the problem can be solved efficiently (as opposed to a...

Parallelism and Greedy Algorithms

A number of greedy algorithms are examined <and are shown to be probably inherently sequential. Greedy algorithms are presented for finding a maximal path, for finding a . maximal set of disjoint paths in a layered dag, and for finding the largest induced subgraph of a graph that has all vertices of degree at least Ic. It is shown that for all of these algorithms, the problem of determining if ...

Distributed Greedy Pursuit Algorithms

For compressed sensing over arbitrarily connected networks, we consider the problem of estimating underlying sparse signals in a distributed manner. We introduce a new signal model that helps to describe inter-signal correlation among connected nodes. Based on this signal model along with a brief survey of existing greedy algorithms, we develop distributed greedy algorithms with low communicati...

Greedy algorithms for prediction

In many prediction problems, it is not uncommon that the number of variables used to construct a forecast is of the same order of magnitude as the sample size, if not larger. We then face the problem of constructing a prediction in the presence of potentially large estimation error. Control of the estimation error is either achieved by selecting variables or combining all the variables in some ...