Journal of the ACM

We define a generalization of the classical secretary problem called the matroid secretary problem. In this problem, the elements of a matroid are presented to an online algorithm in uniformly random order. When an element arrives, the algorithm ...

In the decremental single-source shortest paths (SSSP) problem, we want to maintain the distances between a given source node s and every other node in an n-node m-edge graph G undergoing edge deletions. While its static counterpart can be solved in ...

We introduce a new and natural algebraic proof system, whose complexity measure is essentially the algebraic circuit size of Nullstellensatz certificates. This enables us to exhibit close connections between effective Nullstellensatzë, proof complexity, ...

This is an erratum for the article “Limited-Use Atomic Snapshots with Polylogarithmic Step Complexity” published in J. ACM 62(1): 3:1-3:22 (2015). The implementation of a MaxArray_k×h object in Algorithm 2 does not guarantee linearizability. We give here ...

Indistinguishability obfuscation (IO) is a tremendous notion, powerful enough to give rise to almost any known cryptographic object. Prior candidate IO constructions were based on specific assumptions on algebraic objects called multi-linear graded ...

We prove that any non-adaptive algorithm that tests whether an unknown Boolean function f:{0,1}ⁿ→ {0,1} is a k-junta or ϵ-far from every k-junta must make Ω^˜(k^3/2) / ϵ) many queries for a wide range of parameters k and ϵ. Our result dramatically ...

The goal of this article is to identify fundamental limitations on how efficiently algorithms implemented on platforms such as MapReduce and Hadoop can compute the central problems in motivating application domains, such as graph connectivity problems. ...

We present a new framework for solving optimization problems with a diseconomy of scale. In such problems, our goal is to minimize the cost of resources used to perform a certain task. The cost of resources grows superlinearly, as x^q, q≥ 1, with the ...

A metric tree embedding of expected stretch α ≥ 1 maps a weighted n-node graph G = (V, E, ω) to a weighted tree T = (V_T, E_T , ω_T) with V ⊑ V_T such that, for all v,w ∈ V, dist(v, w, G) ≤ dist(v, w, T), and E[dist(v, w, T)] ≤ α dist(v, w, G). Such ...

Tasks and objects are two predominant ways of specifying distributed problems where processes should compute outputs based on their inputs. Roughly speaking, a task specifies, for each set of processes and each possible assignment of input values, their ...