Greedy algorithms and Zipf laws
We consider a simple model of firm/city/etc growth based on a multi-item criterion: whenever entity B fares better than entity A on a subset of M items out of K, the agent originally in A moves to B. We solve the model analytically in the cases K = 1 and . The resulting stationary distribution of...
Main Authors: | , |
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Format: | Journal article |
Language: | English |
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IOP Publishing
2018
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_version_ | 1797084148438925312 |
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author | Moran, J Bouchaud, J-P |
author_facet | Moran, J Bouchaud, J-P |
author_sort | Moran, J |
collection | OXFORD |
description | We consider a simple model of firm/city/etc growth based on a multi-item criterion: whenever entity B fares better than entity A on a subset of M items out of K, the agent originally in A moves to B. We solve the model analytically in the cases K = 1 and . The resulting stationary distribution of sizes is generically a Zipf-law provided M > K/2. When , no selection occurs and the size distribution remains thin-tailed. In the special case M = K, one needs to regularize the problem by introducing a small 'default' probability phgr. We find that the stationary distribution has a power-law tail that becomes a Zipf-law when . The approach to the stationary state can also be characterized, with strong similarities with a simple 'aging' model considered by Barrat and Mézard. |
first_indexed | 2024-03-07T01:51:18Z |
format | Journal article |
id | oxford-uuid:9a2c7f8f-cfee-4d0f-a1e1-1dbb7d4a0fd1 |
institution | University of Oxford |
language | English |
last_indexed | 2024-03-07T01:51:18Z |
publishDate | 2018 |
publisher | IOP Publishing |
record_format | dspace |
spelling | oxford-uuid:9a2c7f8f-cfee-4d0f-a1e1-1dbb7d4a0fd12022-03-27T00:19:36ZGreedy algorithms and Zipf lawsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:9a2c7f8f-cfee-4d0f-a1e1-1dbb7d4a0fd1EnglishSymplectic ElementsIOP Publishing2018Moran, JBouchaud, J-PWe consider a simple model of firm/city/etc growth based on a multi-item criterion: whenever entity B fares better than entity A on a subset of M items out of K, the agent originally in A moves to B. We solve the model analytically in the cases K = 1 and . The resulting stationary distribution of sizes is generically a Zipf-law provided M > K/2. When , no selection occurs and the size distribution remains thin-tailed. In the special case M = K, one needs to regularize the problem by introducing a small 'default' probability phgr. We find that the stationary distribution has a power-law tail that becomes a Zipf-law when . The approach to the stationary state can also be characterized, with strong similarities with a simple 'aging' model considered by Barrat and Mézard. |
spellingShingle | Moran, J Bouchaud, J-P Greedy algorithms and Zipf laws |
title | Greedy algorithms and Zipf laws |
title_full | Greedy algorithms and Zipf laws |
title_fullStr | Greedy algorithms and Zipf laws |
title_full_unstemmed | Greedy algorithms and Zipf laws |
title_short | Greedy algorithms and Zipf laws |
title_sort | greedy algorithms and zipf laws |
work_keys_str_mv | AT moranj greedyalgorithmsandzipflaws AT bouchaudjp greedyalgorithmsandzipflaws |