Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | ACM Digital Library |
|---|---|
| Author | Hanusse, Nicolas Maabout, Sofian Wanko, Patrick Kamnang |
| Abstract | Let T be a table of n points described by a set of d attributes/dimensions. Let p, q ∈ T. p dominates q iff it is better than q in every dimension and there exists at least one attribute for which p is strictly better than p. p is a skyline point of T iff it is not dominated by any point of T. A skyline query returns the set of all skyline points. In order to integrate Skyline queries into database management systems, deriving an estimation of the skyline cardinality is important for query optimization purposes. We propose techniques for estimating skyline cardinality when data distribution is known. We first provide an unbiased estimator which requires one traversal of the whole data which is much faster than computing the exact skyline. Then, we show that this estimator can be used on a sample of the underlying data while preserving the estimation quality, i.e., it is still unbiased. Next, we provide a convergent estimator which does not require any data access but the data distribution. It estimates skyline cardinality expectation for those data sets respecting data distribution. The advantages of these solutions are their ease of implementation and, by contrast to other proposals, no costly subskyline queries are required. Our solutions are implemented and some experiments are reported showing both the accuracy of the estimations and the execution time efficiency by which they are obtained. |
| Starting Page | 125 |
| Ending Page | 134 |
| Page Count | 10 |
| File Format | |
| ISBN | 9781450341189 |
| DOI | 10.1145/2938503.2938531 |
| Language | English |
| Publisher | Association for Computing Machinery (ACM) |
| Publisher Date | 2016-07-11 |
| Publisher Place | New York |
| Access Restriction | Subscribed |
| Subject Keyword | Algorithms Estimation Expectation Sampling Skyline cardinality |
| Content Type | Text |
| Resource Type | Article |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|