UMBC ebiquity
2015 June

Archive for June, 2015

Hot Stuff at ColdStart

June 8th, 2015, by Tim Finin, posted in AI, KR, NLP, NLP, Ontologies

Cold Start

Coldstart is a task in the NIST Text Analysis Conference’s Knowledge Base Population suite that combines entity linking and slot filling to populate an empty knowledge base using a predefined ontology for the facts and relations. This paper describes a system developed by the Human Language Technology Center of Excellence at Johns Hopkins University for the 2014 Coldstart task.

Tim Finin, Paul McNamee, Dawn Lawrie, James Mayfield and Craig Harman, Hot Stuff at Cold Start: HLTCOE participation at TAC 2014, 7th Text Analysis Conference, National Institute of Standards and Technology, Nov. 2014.

The JHU HLTCOE participated in the Cold Start task in this year’s Text Analysis Conference Knowledge Base Population evaluation. This is our third year of participation in the task, and we continued our research with the KELVIN system. We submitted experimental variants that explore use of forward-chaining inference, slightly more aggressive entity clustering, refined multiple within-document conference, and prioritization of relations extracted from news sources.

Platys: From Position to Place-Oriented Mobile Computing

June 8th, 2015, by Tim Finin, posted in AI, KR, Machine Learning, Mobile Computing, Ontologies

The NSF-sponsored Platys project explored the idea that places are more than just GPS coordinates. They are concepts rich with semantic information, including people, activities, roles, functions, time and purpose. Our mobile phones can learn to recognize the places we are in and use information about them to provide better services.

Laura Zavala, Pradeep K. Murukannaiah, Nithyananthan Poosamani, Tim Finin, Anupam Joshi, Injong Rhee and Munindar P. Singh, Platys: From Position to Place-Oriented Mobile Computing, AI Magazine, v36, n2, 2015.

The Platys project focuses on developing a high-level, semantic notion of location called place. A place, unlike a geospatial position, derives its meaning from a user’s actions and interactions in addition to the physical location where it occurs. Our aim is to enable the construction of a large variety of applications that take advantage of place to render relevant content and functionality and, thus, improve user experience. We consider elements of context that are particularly related to mobile computing. The main problems we have addressed to realize our place-oriented mobile computing vision are representing places, recognizing places, and engineering place-aware applications. We describe the approaches we have developed for addressing these problems and related subproblems. A key element of our work is the use of collaborative information sharing where users’ devices share and integrate knowledge about places. Our place ontology facilitates such collaboration. Declarative privacy policies allow users to specify contextual features under which they prefer to share or not share their information.

UMBC Schema Free Query system on ESWC Schema-agnostic Queries over Linked Data

June 7th, 2015, by Tim Finin, posted in Machine Learning, NLP, RDF, Semantic Web

This year’s ESWC Semantic Web Evaluation Challenge track had a task on Schema-agnostic Queries over Linked Data: SAQ-2015. The idea is to support a SPARQL-like query language that does not require knowing the underlying graph schema nor the URIs to use for terms and individuals, as in the follwing examples.

 SELECT ?y {BillClinton hasDaughter ?x. ?x marriedTo ?y.}

 SELECT ?x {?x isA book. ?x by William_Goldman.
            ?x has_pages ?p. FILTER (?p > 300)}

We adapted our Schema Free Querying system to the task as described in the following paper.

Zareen Syed, Lushan Han, Muhammad Mahbubur Rahman, Tim Finin, James Kukla and Jeehye Yun, UMBC_Ebiquity-SFQ: Schema Free Querying System, ESWC Semantic Web Evaluation Challenge, Extended Semantic Web Conference, June 2015.

Users need better ways to explore large complex linked data resources. Using SPARQL requires not only mastering its syntax and semantics but also understanding the RDF data model, the ontology and URIs for entities of interest. Natural language question answering systems solve the problem, but these are still subjects of research. The Schema agnostic SPARQL queries task defined in SAQ-2015 challenge consists of schema-agnostic queries following the syntax of the SPARQL standard, where the syntax and semantics of operators are maintained, while users are free to choose words, phrases and entity names irrespective of the underlying schema or ontology. This combination of query skeleton with keywords helps to remove some of the ambiguity. We describe our framework for handling schema agnostic or schema free queries and discuss enhancements to handle the SAQ-2015 challenge queries. The key contributions are the robust methods that combine statistical association and semantic similarity to map user terms to the most appropriate classes and properties used in the underlying ontology and type inference for user input concepts based on concept linking.

Interactive Knowledge Base Population

June 6th, 2015, by Tim Finin, posted in AI, NLP

Travis Wolfe, Mark Dredze, James Mayfield, Paul McNamee, Craig Harman, Tim Finin and Benjamin Van Durme, Interactive Knowledge Base Population, arXiv:1506.00301 [cs.AI], May 2015.

Most work on building knowledge bases has focused on collecting entities and facts from as large a collection of documents as possible. We argue for and describe a new paradigm where the focus is on a high-recall extraction over a small collection of documents under the supervision of a human expert, that we call Interactive Knowledge Base Population (IKBP).

Querying RDF Data with Text Annotated Graphs

June 6th, 2015, by Tim Finin, posted in Big data, Database, Machine Learning, RDF, Semantic Web

New paper: Lushan Han, Tim Finin, Anupam Joshi and Doreen Cheng, Querying RDF Data with Text Annotated Graphs, 27th International Conference on Scientific and Statistical Database Management, San Diego, June 2015.

Scientists and casual users need better ways to query RDF databases or Linked Open Data. Using the SPARQL query language requires not only mastering its syntax and semantics but also understanding the RDF data model, the ontology used, and URIs for entities of interest. Natural language query systems are a powerful approach, but current techniques are brittle in addressing the ambiguity and complexity of natural language and require expensive labor to supply the extensive domain knowledge they need. We introduce a compromise in which users give a graphical “skeleton” for a query and annotates it with freely chosen words, phrases and entity names. We describe a framework for interpreting these “schema-agnostic queries” over open domain RDF data that automatically translates them to SPARQL queries. The framework uses semantic textual similarity to find mapping candidates and uses statistical approaches to learn domain knowledge for disambiguation, thus avoiding expensive human efforts required by natural language interface systems. We demonstrate the feasibility of the approach with an implementation that performs well in an evaluation on DBpedia data.

Discovering and Querying Hybrid Linked Data

June 5th, 2015, by Tim Finin, posted in Big data, KR, Machine Learning, Semantic Web


New paper: Zareen Syed, Tim Finin, Muhammad Rahman, James Kukla and Jeehye Yun, Discovering and Querying Hybrid Linked Data, Third Workshop on Knowledge Discovery and Data Mining Meets Linked Open Data, held in conjunction with the 12th Extended Semantic Web Conference, Portoroz Slovenia, June 2015.

In this paper, we present a unified framework for discovering and querying hybrid linked data. We describe our approach to developing a natural language query interface for a hybrid knowledge base Wikitology, and present that as a case study for accessing hybrid information sources with structured and unstructured data through natural language queries. We evaluate our system on a publicly available dataset and demonstrate improvements over a baseline system. We describe limitations of our approach and also discuss cases where our system can complement other structured data querying systems by retrieving additional answers not available in structured sources.

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