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Second 2012 (vol. 5 no. 2)
pp. 117-129
A. Poulovassilis, London Knowledge Lab., Birkbeck, Univ. of London, London, UK
P. Selmer, London Knowledge Lab., Birkbeck, Univ. of London, London, UK
P. T. Wood, Dept. of Comput. Sci. & Inf. Syst., Birkbeck, Univ. of London, London, UK
This paper discusses the provision of flexible querying facilities over heterogeneous data arising from lifelong learners' educational and work experiences. A key aim of such querying facilities is to allow learners to identify possible choices for their future learning and professional development by seeing what others have done. We motivate and describe the development of a prototype system, called ApproxRelax, that provides users with a graphical facility for incrementally constructing their queries and that supports both query approximation and query relaxation, thus allowing for flexible matching of users' queries against the data provided by other learners. We show how the system is able to return results in ranked order of their “distance” from the user's query. Our approach is novel both in its aim of supporting lifelong learners in reflecting on their learning and career choices, and also in its technical foundations that combine for the first time query approximation and query relaxation techniques for querying semistructured data.

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Index Terms:
Measurement,Educational institutions,Approximation methods,Prototypes,Engineering profession,Information systems,Resource description framework,timelines.,Lifelong learning,careers guidance,semantic web,flexible querying
A. Poulovassilis, P. Selmer, P. T. Wood, "Flexible Querying of Lifelong Learner Metadata," IEEE Transactions on Learning Technologies, vol. 5, no. 2, pp. 117-129, Second 2012, doi:10.1109/TLT.2011.38
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