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20112026
most citedFast Exact k-Means, k-Medians and Bregman Divergence Clustering in 1D

48 citations · 181 across the 49 of their papers we have counts for

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cs.DS2026

The Binary Tree Mechanism is Optimal for Differentially Private Continual Counting

Konstantina Bairaktari, Kasper Green Larsen, Markus Engelund Dahl

Private continual counting is a fundamental problem in differential privacy: given a binary stream of length , where each corresponds to the contribution of one individual,…

cs.DS2023

Optimal Non-Adaptive Cell Probe Dictionaries and Hashing

Kasper Green Larsen, Rasmus Pagh, Giuseppe Persiano +3

We present a simple and provably optimal non-adaptive cell probe data structure for the static dictionary problem. Our data structure supports storing a set of n key-value pairs fr…

cs.DS2023

Sublinear Time Shortest Path in Expander Graphs

Noga Alon, Allan Grønlund, Søren Fuglede Jørgensen +1

Computing a shortest path between two nodes in an undirected unweighted graph is among the most basic algorithmic tasks. Breadth first search solves this problem in linear time, wh…

cs.DS2023

Invertible Bloom Lookup Tables with Less Memory and Randomness

Nils Fleischhacker, Kasper Green Larsen, Maciej Obremski +1

In this work we study Invertible Bloom Lookup Tables (IBLTs) with small failure probabilities. IBLTs are highly versatile data structures that have found applications in set reconc…

cs.DS2023

Super-Logarithmic Lower Bounds for Dynamic Graph Problems

Kasper Green Larsen, Huacheng Yu

In this work, we prove a unconditional lower bound on the maximum of the query time and update time for dynamic data structures supporting reachability quer…

cs.DS2023

Sparse Dimensionality Reduction Revisited

Mikael Møller Høgsgaard, Lion Kamma, Kasper Green Larsen +2

The sparse Johnson-Lindenstrauss transform is one of the central techniques in dimensionality reduction. It supports embedding a set of points in into $m=O(\vare…

cs.DS2022

Hierarchical Categories in Colored Searching

Peyman Afshani, Rasmus Killman, Kasper Green Larsen

In colored range counting (CRC), the input is a set of points where each point is assigned a ``color'' (or a ``category'') and the goal is to store them in a data structure such th…

cs.DS2022

Barriers for Faster Dimensionality Reduction

Ora Nova Fandina, Mikael Møller Høgsgaard, Kasper Green Larsen

The Johnson-Lindenstrauss transform allows one to embed a dataset of points in into while preserving the pairwise distance between any pair of po…

cs.DS2022

Fast Discrepancy Minimization with Hereditary Guarantees

Kasper Green Larsen

Efficiently computing low discrepancy colorings of various set systems, has been studied extensively since the breakthrough work by Bansal (FOCS 2010), who gave the first polynomia…

cs.DS2022★ 1 cited

The Fast Johnson-Lindenstrauss Transform is Even Faster

Ora Nova Fandina, Mikael Møller Høgsgaard, Kasper Green Larsen

The seminal Fast Johnson-Lindenstrauss (Fast JL) transform by Ailon and Chazelle (SICOMP'09) embeds a set of points in -dimensional Euclidean space into optimal $k=O(\vareps…

cs.DS2022★ 2 cited

Stronger 3SUM-Indexing Lower Bounds

Eldon Chung, Kasper Green Larsen

The SUM-Indexing problem was introduced as a data structure version of the SUM problem, with the goal of proving strong conditional lower bounds for static data structures vi…

cs.DS2022★ 4 cited

Towards Optimal Lower Bounds for k-median and k-means Coresets

Vincent Cohen-Addad, Kasper Green Larsen, David Saulpic +1

Given a set of points in a metric space, the -clustering problem consists of finding a set of points called centers, such that the sum of distances raised to the power o…

cs.DS2021★ 1 cited

Optimality of the Johnson-Lindenstrauss Dimensionality Reduction for Practical Measures

Yair Bartal, Ora Nova Fandina, Kasper Green Larsen

It is well known that the Johnson-Lindenstrauss dimensionality reduction method is optimal for worst case distortion. While in practice many other methods and heuristics are used,…

cs.DS2021

CountSketches, Feature Hashing and the Median of Three

Kasper Green Larsen, Rasmus Pagh, Jakub Tětek

In this paper, we revisit the classic CountSketch method, which is a sparse, random projection that transforms a (high-dimensional) Euclidean vector to a vector of dimension $(…

cs.DS2020

Further Unifying the Landscape of Cell Probe Lower Bounds

Kasper Green Larsen, Jonathan Lindegaard Starup, Jesper Steensgaard

In a landmark paper, Pǎtraşcu demonstrated how a single lower bound for the static data structure problem of reachability in the butterfly graph, could be used to derive a wealth o…

cs.DS2019

Optimal Learning of Joint Alignments with a Faulty Oracle

Kasper Green Larsen, Michael Mitzenmacher, Charalampos E. Tsourakakis

We consider the following problem, which is useful in applications such as joint image and shape alignment. The goal is to recover discrete variables $g_i \in \{0, \ldots, k-1\…

cs.DS2019

Lower Bounds for Oblivious Near-Neighbor Search

Kasper Green Larsen, Tal Malkin, Omri Weinstein +1

We prove an lower bound on the dynamic cell-probe complexity of statistically approximate-near-neighbor search () over…

cs.DS2019★ 4 cited

Lower Bounds for Multiplication via Network Coding

Peyman Afshani, Casper Benjamin Freksen, Lior Kamma +1

Multiplication is one of the most fundamental computational problems, yet its true complexity remains elusive. The best known upper bound, by Fürer, shows that two -bit numbers…

cs.DS2018

The Query Complexity of a Permutation-Based Variant of Mastermind

Peyman Afshani, Manindra Agrawal, Benjamin Doerr +3

We study the query complexity of a permutation-based variant of the guessing game Mastermind. In this variant, the secret is a pair which consists of a binary string $z \in…

cs.DS2018★ 1 cited

Lower Bounds for External Memory Integer Sorting via Network Coding

Alireza Farhadi, MohammadTaghi Hajiaghayi, Kasper Green Larsen +1

Sorting extremely large datasets is a frequently occuring task in practice. These datasets are usually much larger than the computer's main memory; thus external memory sorting alg…

cs.DS2018

Lower Bounds for Oblivious Data Structures

Riko Jacob, Kasper Green Larsen, Jesper Buus Nielsen

An oblivious data structure is a data structure where the memory access patterns reveals no information about the operations performed on it. Such data structures were introduced b…

cs.DS2018★ 2 cited

A Faster External Memory Priority Queue with DecreaseKeys

Shunhua Jiang, Kasper Green Larsen

A priority queue is a fundamental data structure that maintains a dynamic set of (key, priority)-pairs and supports Insert, Delete, ExtractMin and DecreaseKey operations. In the ex…

cs.DS2018

Upper and lower bounds for dynamic data structures on strings

Raphael Clifford, Allan Grønlund, Kasper Green Larsen +1

We consider a range of simply stated dynamic data structure problems on strings. An update changes one symbol in the input and a query asks us to compute some function of the patte…

cs.DS2017

Tight Cell Probe Bounds for Succinct Boolean Matrix-Vector Multiplication

Diptarka Chakraborty, Lior Kamma, Kasper Green Larsen

The conjectured hardness of Boolean matrix-vector multiplication has been used with great success to prove conditional lower bounds for numerous important data structure problems,…