Cardinality Estimation: Difference between revisions

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(Created page with "{{DISPLAYTITLE:Cardinality Estimation (Cardinality Estimation)}} == Description == Given a multiset of (possibly hashed) values, estimate the number of distinct elements of the multiset. Of interest is minimizing storage usage. == Parameters == <pre>N: number of values in multiset n: cardinality of multiset (not known)</pre> == Table of Algorithms == {| class="wikitable sortable" style="text-align:center;" width="100%" ! Name !! Year !! Time !! Space !! Approxi...")
 
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== Parameters ==  
== Parameters ==  


<pre>N: number of values in multiset
N: number of values in multiset
n: cardinality of multiset (not known)</pre>
 
n: cardinality of multiset (not known)


== Table of Algorithms ==  
== Table of Algorithms ==  

Revision as of 12:02, 15 February 2023

Description

Given a multiset of (possibly hashed) values, estimate the number of distinct elements of the multiset. Of interest is minimizing storage usage.

Parameters

N: number of values in multiset

n: cardinality of multiset (not known)

Table of Algorithms

Name Year Time Space Approximation Factor Model Reference
Naive solution 1940 $O(N)$ $O(n)$ Exact Deterministic
Flajolet–Martin algorithm 1984 $O(N)$ $O(log n)$ Randomized Time & Space
LogLog algorithm 2003 $O(N)$ $O(log(log(n)$)) Randomized Time & Space
HyperLogLog algorithm 2007 $O(N)$ $O(eps^{-2}*log(log(n)$))+log(n)) Randomized Time & Space
HyperLogLog++ 2014 $O(N)$ $O(eps^{-2}*log(log(n)$))+log(n)) Randomized Time

Time Complexity graph

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Space Complexity graph

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Pareto Decades graph

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