A Systematic Literature Review of Linked Data-based Recommender Systems

Recommender Systems (RS) are software tools that use analytic technologies to suggest different items of interest to an end user. Linked Data is a set of best practices for publishing and connecting structured data on the Web. This paper presents a systematic literature review to summarize the state of the art in recommender systems that use structured data published as Linked Data for providing recommendations of items from diverse domains. It considers the most relevant research problems addressed and classifies RS according to how Linked Data has been used to provide recommendations. Furthermore, it analyzes contributions, limitations, application domains, evaluation techniques, and directions proposed for future research. We found that there are still many open challenges with regard to RS based on Linked Data in order to be efficient for real applications. The main ones are personalization of recommendations; use of more datasets considering the heterogeneity introduced; creation of new hybrid RS for adding information; definition of more advanced similarity measures that take into account the large amount of data in Linked Data datasets; and implementation of testbeds to study evaluation techniques and to assess the accuracy scalability and computational complexity of RS

Content Based Cross-Domain Recommendation Using Linked Open Data

A recommender system, irrespective of theapproach that has been used to implement it suffers fromthe cold-start situation. Not being able to predict items to anew user due to not having access to his previouspreferences, and not being able to recommend a new item tousers due to not having any prior ratings on theparticular item is the two cold-start problems. Even thoughcontent-based recommender systems are immune to itemcold-start problem, they are comparatively less used due tolack of up-to-date data sources that provide item featuresand also due to the high amount of pre-processing requiredwhen using existing data sources for retrieving meta-data.In this paper we present a content-based cross domainrecommendation system using Linked Open Data toaddress the issue of cold-start situation. The evaluationproves that this approach can be used as a solution to a coldstartsituation and also the prevailing issue of content-basedrecommender systems which forced them to take thebackseat will no longer be applicable when Linked OpenData is used

Doporučovací systém pro knihy založený na Linked Open Datech

Tato bakalářská práce se zaměřuje na použití metod doporučovacích systémů společně s Open Linked Data v doméně knih. Po důkladné analýze vícero dos- tupných zdrojů otevřených dat bylo usouzeno, že data dostatečné velikosti a kval- ity již existují. Po rozboru struktury těchto dat byl na základě získaných informací ze zdroje Wikidata vytvořen doporučovací systém ve formě webové aplikace. De- sign aplikace umožňuje rozšíření o další zdroje otevřených dat. Byl použit nový přístup pro generování doporučení, který využívá vícejazyčných tagů vytěžených z Wikipedie. Ukázali jsme, že je opravdu možné použít doporučovací systémy společně s Open Linked Data, ale díky zvýšené řídkosti dat je potřeba upravit standardní metody doporučovacích algoritmů odpovídajícím způsobem.This thesis focuses on using recommender system's methods on Linked Open Data in a domain of books. After thorough analysis of multiple available Linked Open Data sets, we have concluded that data sets of sufficient size and quality already exist. Together with careful analysis of the structure and quality of the data, recommender system web application has been developed based on retrieved data from a Wikidata endpoint. The application design allows an incorporation of data from multiple sources. A novel approach for generating recommendations utilizing multi language tags extracted from Wikipedia was used. We have shown that it is possible and viable to use recommender systems on top of the Linked Open Data, but the common recommender system's algorithms have to be modified in order to deal with a huge amount of sparsity in the data.Department of Software EngineeringKatedra softwarového inženýrstvíMatematicko-fyzikální fakultaFaculty of Mathematics and Physic

Semantic data mining and linked data for a recommender system in the AEC industry

Even though it can provide design teams with valuable performance insights and enhance decision-making, monitored building data is rarely reused in an effective feedback loop from operation to design. Data mining allows users to obtain such insights from the large datasets generated throughout the building life cycle. Furthermore, semantic web technologies allow to formally represent the built environment and retrieve knowledge in response to domain-specific requirements. Both approaches have independently established themselves as powerful aids in decision-making. Combining them can enrich data mining processes with domain knowledge and facilitate knowledge discovery, representation and reuse. In this article, we look into the available data mining techniques and investigate to what extent they can be fused with semantic web technologies to provide recommendations to the end user in performance-oriented design. We demonstrate an initial implementation of a linked data-based system for generation of recommendations

Ontology-Based Recommendation of Editorial Products

Major academic publishers need to be able to analyse their vast catalogue of products and select the best items to be marketed in scientific venues. This is a complex exercise that requires characterising with a high precision the topics of thousands of books and matching them with the interests of the relevant communities. In Springer Nature, this task has been traditionally handled manually by publishing editors. However, the rapid growth in the number of scientific publications and the dynamic nature of the Computer Science landscape has made this solution increasingly inefficient. We have addressed this issue by creating Smart Book Recommender (SBR), an ontology-based recommender system developed by The Open University (OU) in collaboration with Springer Nature, which supports their Computer Science editorial team in selecting the products to market at specific venues. SBR recommends books, journals, and conference proceedings relevant to a conference by taking advantage of a semantically enhanced representation of about 27K editorial products. This is based on the Computer Science Ontology, a very large-scale, automatically generated taxonomy of research areas. SBR also allows users to investigate why a certain publication was suggested by the system. It does so by means of an interactive graph view that displays the topic taxonomy of the recommended editorial product and compares it with the topic-centric characterization of the input conference. An evaluation carried out with seven Springer Nature editors and seven OU researchers has confirmed the effectiveness of the solution

What’s going on in my city? Recommender systems and electronic participatory budgeting

In this paper, we present electronic participatory budgeting (ePB) as a novel application domain for recommender systems. On public data from the ePB platforms of three major US cities – Cambridge, Miami and New York City–, we evaluate various methods that exploit heterogeneous sources and models of user preferences to provide personalized recommendations of citizen proposals. We show that depending on characteristics of the cities and their participatory processes, particular methods are more effective than others for each city. This result, together with open issues identified in the paper, call for further research in the area

Collaborative recommendations with content-based filters for cultural activities via a scalable event distribution platform

Nowadays, most people have limited leisure time and the offer of (cultural) activities to spend this time is enormous. Consequently, picking the most appropriate events becomes increasingly difficult for end-users. This complexity of choice reinforces the necessity of filtering systems that assist users in finding and selecting relevant events. Whereas traditional filtering tools enable e.g. the use of keyword-based or filtered searches, innovative recommender systems draw on user ratings, preferences, and metadata describing the events. Existing collaborative recommendation techniques, developed for suggesting web-shop products or audio-visual content, have difficulties with sparse rating data and can not cope at all with event-specific restrictions like availability, time, and location. Moreover, aggregating, enriching, and distributing these events are additional requisites for an optimal communication channel. In this paper, we propose a highly-scalable event recommendation platform which considers event-specific characteristics. Personal suggestions are generated by an advanced collaborative filtering algorithm, which is more robust on sparse data by extending user profiles with presumable future consumptions. The events, which are described using an RDF/OWL representation of the EventsML-G2 standard, are categorized and enriched via smart indexing and open linked data sets. This metadata model enables additional content-based filters, which consider event-specific characteristics, on the recommendation list. The integration of these different functionalities is realized by a scalable and extendable bus architecture. Finally, focus group conversations were organized with external experts, cultural mediators, and potential end-users to evaluate the event distribution platform and investigate the possible added value of recommendations for cultural participation