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An analysis of NP-completeness in novelty and diversity ranking

Ben Carterette
2010 Information retrieval (Boston)  
This is clearly an instance of Minimum Set Cover and therefore NP-complete in general. S-recall.  ...  A useful ability for search engines is to be able to rank objects with novelty and diversity: the top k documents retrieved should cover possible interpretations of a query with some distribution, or should  ...  Conclusion We have argued that NP-complete evaluation and optimization can be a serious problem for retrieval systems.  ... 
doi:10.1007/s10791-010-9157-1 fatcat:grjv435uvfdcbexeqpntkxnffm

An Analysis of NP-Completeness in Novelty and Diversity Ranking [chapter]

Ben Carterette
2009 Lecture Notes in Computer Science  
This is clearly an instance of Minimum Set Cover and therefore NP-complete in general. S-recall.  ...  A useful ability for search engines is to be able to rank objects with novelty and diversity: the top k documents retrieved should cover possible interpretations of a query with some distribution, or should  ...  Conclusion We have argued that NP-complete evaluation and optimization can be a serious problem for retrieval systems.  ... 
doi:10.1007/978-3-642-04417-5_18 fatcat:cacazoasn5bk7j7dcanuv4bcha

Introduction to special issue on the second international conference on the theory of information retrieval

Leif Azzopardi, Dawei Song, Gabriella Kazai, Stephen Robertson, Stefan Rüger, Milad Shokouhi, Emine Yilmaz
2010 Information retrieval (Boston)  
Acknowledgments We would like to thank all the reviewers of the ICTIR 2009 conference and the reviewers of this special issue.  ...  We would also like to thank all the local organizers, student volunteers, sponsors and participants for their contribution to the success of the ICTIR 2009 conference.  ...  In An Analysis of NP-Completeness in Novelty and Diversity Ranking, Carterette investigates measures of novelty and diversity by performing a detailed analysis of the problems of computing such measures  ... 
doi:10.1007/s10791-010-9142-8 fatcat:ox7epuxp45h2fd432babvgtliu

Novelty based Ranking of Human Answers for Community Questions

Adi Omari, David Carmel, Oleg Rokhlenko, Idan Szpektor
2016 Proceedings of the 39th International ACM SIGIR conference on Research and Development in Information Retrieval - SIGIR '16  
An experiment over a collection of Health questions, using a manually annotated gold-standard dataset, shows that considering novelty for answer ranking improves the quality of the ranked answer list.  ...  Answers are ranked in a greedy manner, taking into account their relevance to the question as well as their novelty compared to higher ranked answers and their coverage of important aspects.  ...  NOVELTY-BASED ANSWER RANKING In this work we propose an answer ranking solution that focuses on diversity and novelty notions of answers on top of relevance.  ... 
doi:10.1145/2911451.2911506 dblp:conf/sigir/OmariCRS16 fatcat:pn43qih27rhwnhbffixa2pnobi

Preference based evaluation measures for novelty and diversity

Praveen Chandar, Ben Carterette
2013 Proceedings of the 36th international ACM SIGIR conference on Research and development in information retrieval - SIGIR '13  
Novel and diverse document ranking is an effective strategy that involves reducing redundancy in a ranked list to maximize the amount of novel and relevant information available to users.  ...  Evaluation for novelty and diversity typically involves an assessor judging each document for relevance against a set of pre-identified subtopics, which may be disambiguations of the query, facets of an  ...  Any opinions, findings and conclusions or recommendations expressed in this material are the authors' and do not necessarily reflect those of the sponsor.  ... 
doi:10.1145/2484028.2484094 dblp:conf/sigir/ChandarC13 fatcat:znw62skuv5gyhe3kqcq4g6c5t4

Search Result Diversification

Rodrygo L. T. Santos, Craig Macdonald, Iadh Ounis
2015 Foundations and Trends in Information Retrieval  
In particular, producing an ideal ranking for normalising such metrics is an NP-hard problem, as discussed in §2.5.  ...  In its general form, this is an NP-hard problem [Carterette, 2009] , for which an extensive body of research has been devoted in recent years.  ... 
doi:10.1561/1500000040 fatcat:g4vxxda6u5aaljeqg6n47lushu

On the role of novelty for search result diversification

Rodrygo L. T. Santos, Craig Macdonald, Iadh Ounis
2011 Information retrieval (Boston)  
In this paper, we challenge this common intuition and thoroughly investigate the actual role of novelty for search result diversification, based upon the framework provided by the diversity task of the  ...  Finally, through a comprehensive analysis with simulated rankings of various quality, we demonstrate that, although inherently limited by the performance of the initial ranking, novelty plays a role at  ...  and is therefore NP-hard (Agrawal et al.  ... 
doi:10.1007/s10791-011-9180-x fatcat:na75z3sqljdxxa3z3q2tga3bwq

Learning to rank relevant and novel documents through user feedback

Abhimanyu Lad, Yiming Yang
2010 Proceedings of the 19th ACM international conference on Information and knowledge management - CIKM '10  
The ranked list is produced to maximize the weighted coverage of these surrogate nuggets. The optimization of such coverage-based metrics is known to be NP-hard.  ...  Therefore, our approach uses observable query and document features (words and named entities) as surrogates for nuggets, whose weights are learned based on user feedback in an iterative search session  ...  We show that the ranking problem is NP-hard, and use mathematical as well as empirical analysis to demonstrate that a simple greedy algorithm achieves good performance with respect to EGU.  ... 
doi:10.1145/1871437.1871499 dblp:conf/cikm/LadY10 fatcat:p2ondewxvbg5dnnslanzjzyoku

On the Complexity of Query Result Diversification

Ting Deng, Wenfei Fan
2014 ACM Transactions on Database Systems  
Subsets of Q(D) are ranked by an objective function defined in terms of relevance and diversity.  ...  We identify three problems in connection with query result diversification, to determine whether there exists a set of k tuples that is ranked above a bound with respect to relevance and diversity, to  ...  For its upper bound, we show that DRP(LQ, F (·)) is in coNP when LQ is ∃FO + by developing an NP algorithm to check whether rank(U ) > r for a given set U and a rank r.  ... 
doi:10.1145/2602136 fatcat:a5t4c5nsujhtvfs3p2k35vsxhu

On the complexity of query result diversification

Ting Deng, Wenfei Fan
2013 Proceedings of the VLDB Endowment  
Subsets of Q(D) are ranked by an objective function defined in terms of relevance and diversity.  ...  We identify three problems in connection with query result diversification, to determine whether there exists a set of k tuples that is ranked above a bound with respect to relevance and diversity, to  ...  For its upper bound, we show that DRP(LQ, F (·)) is in coNP when LQ is ∃FO + by developing an NP algorithm to check whether rank(U ) > r for a given set U and a rank r.  ... 
doi:10.14778/2536354.2536358 fatcat:mrsuoyqjmvfq3dtmemkv333ssm

Yeast Synthetic Biology Platform Generates Novel Chemical Structures as Scaffolds for Drug Discovery

Jens Klein, Jonathan R. Heal, William D. O. Hamilton, Thiamo Boussemghoune, Thomas Østergaard Tange, Fanny Delegrange, Georg Jaeschke, Anaëlle Hatsch, Jutta Heim
2014 ACS Synthetic Biology  
data of all 74 SB compounds, diversity (cluster) analysis comparing the SB compounds with other compound libraries, the identity of genes used in the YACs, and luciferase assay data.  ...  Based on the concept of "coevolution" with target proteins in an intracellular primary survival assay, the identified, mostly scaffold-sized (200−350 MW) compounds, which displayed excellent biological  ...  Forty percent of these compounds exhibited activity in the secondary BMV assay, therefore relating novelty to biologically relevant chemical space. Synthetic Biology Compound Diversity Analysis.  ... 
doi:10.1021/sb400177x pmid:24742115 pmcid:PMC4046787 fatcat:ufmxtdop6fabzhox2bodlnsor4

Novelty and Diversity in Recommender Systems [chapter]

Pablo Castells, Neil J. Hurley, Saul Vargas
2015 Recommender Systems Handbook  
In the present work we propose an Information Retrieval approach to the evaluation and enhacement of novelty and diversity in Recommender Systems.  ...  We also propose a new formalization and unification of the way novelty and diversity are evaluated on Recommender Systems, considering rank and relevance as additional and meaningful aspects for the evaluation  ...  State of the Art In this section we present an extensive analysis of the state of the art to identify and analyze current trends in the study of algorithms and evaluation metrics for IR, novelty and diversity  ... 
doi:10.1007/978-1-4899-7637-6_26 fatcat:53veooy4dzgzxcr3volnel46w4

Answer Diversification for Complex Question Answering on the Web [chapter]

Palakorn Achananuparp, Xiaohua Hu, Tingting He, Christopher C. Yang, Yuan An, Lifan Guo
2010 Lecture Notes in Computer Science  
We present a novel graph ranking model to extract a diverse set of answers for complex questions via random walks over a negative-edge graph.  ...  We assign a negative sign to edge weights in an answer graph to model the redundancy relation among the answer nodes.  ...  This research work is supported in part from the NSF Career grant IIS 0448023, NSF CCF 0905291, NSF IIP 0934197, NSFC 90920005 and the Program of Introducing Talents of Discipline to Universities B07042  ... 
doi:10.1007/978-3-642-13657-3_41 fatcat:7iuvkwwdjradxbfmakzozyodnq

An axiomatic approach for result diversification

Sreenivas Gollapudi, Aneesh Sharma
2009 Proceedings of the 18th international conference on World wide web - WWW '09  
diversity in the results.  ...  Understanding user intent is key to designing an effective ranking system in a search engine.  ...  Acknowledgments We would like to thank Kunal Talwar for helpful discussions, and Panayiotis Tsaparas for providing data and helping us with the classification of product queries.  ... 
doi:10.1145/1526709.1526761 dblp:conf/www/GollapudiS09 fatcat:sfbp2hzwl5bddnwscvpd7t4xzy

Neuronal mechanisms of novelty seeking [article]

Takaya Ogasawara, Fatih Sogukpinar, Kaining Zhang, Yang-Yang Feng, Julia Pai, Ahmad Jezzini, Ilya E Monosov
2021 bioRxiv   pre-print
However, despite the importance of novel visual objects in our daily life, we currently lack an understanding of how primate brain circuits control the motivation to seek out novelty.  ...  In addition to their well-known function in signaling the novelty or familiarity of objects in the current environment, AVMTC neurons reflected the predictions of future novel objects, akin to the way  ...  Here, we performed this analysis on an area by area basis (% of neurons shown in blue) during novelty-inspecting trials ( Figure 1A) .  ... 
doi:10.1101/2021.03.12.435019 fatcat:o5no3wdv5rbrjlsbnhbet73wzi
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