Explicit and implicit trust modeling compatibility and explicit trust link prediction in trust-based recommendation systems

Download

index.pdf

Date

2022-1-31

Author

Demirci, Mehmet Utku

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

191
views

106
downloads

In social networks, trust is a fundamental notion affecting the nature and the strength of ties between individuals. It is also a piece of useful auxiliary information for improving the performance of recommendation systems. The number of ratings given by a user is minimal compared to all items in popular, widely-used e-commerce sites. Therefore, the user-item matrix that is used in collaborative filtering suffers from data sparsity, resulting in poor recommendation quality. Another issue is the cold start problem, which occurs for the inclusion of new users and new items to the system. Trust notion helps alleviate the effect of these problems by providing additional relationships between the users and pointing out strong relationships. Information as to the trust between users can be explicitly available. However, such information is not widely available, and hence implicit trust models have been employed. This work analyzes two sub-problems under trust modeling for recommendation: (1) What is the relationship between explicit and implicit trust scores, are they replaceable? (2) Can the explicit trust in a trust network be modeled? An implicit trust model is presented for the first problem, and the compatibility of implicit and explicit trust scores is analyzed. For the second problem, two different explicit trust models are proposed: Explicit trust modeling through users' rating behavior and explicit trust modeling as a link prediction problem. The performances of the generated prediction models are analyzed on a set of benchmark data sets.

Subject Keywords

Trust modeling, Implicit trust, Explicit trust, Recommendation, Recommender systems, Supervised learning

URI

https://hdl.handle.net/11511/96338

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Trust Modeling in Recommendation Demirci, Mehmet Utku; Karagöz, Pınar (2021-12-09) In social networks, trust is a fundamental notion aecting the na-ture and the strength of ties between individuals. It is also a pieceof useful auxiliary information for improving the performance ofrecommendation systems. The number of ratings given by a user isminimal compared to all items in popular, widely-used e-commercesites. Therefore, the user-item matrix that is used in collaborativeltering suers from data sparsity, resulting in poor recommenda-tion quality. Another issue is the cold start proble...
The relationship between regulatory focus and trust: The roles of regulatory closure and propensity to trust Emirza, Sevgi; Karagonlar, Gökhan (Orta Doğu Teknik Üniversitesi (Ankara, Turkey), 2020-6) Drawing on regulatory focus theory and regulatory closure argument, this study argues that self-regulation mechanisms influence trust among people during anonymous interactions. Prevention focus is generally associated with risk aversion and quest for security and hence expected to induce less trust compared to promotion focus. We proposed and tested the hypothesis that the effect of regulatory focus on trust is moderated by regulatory closure (presence or absence of goal fulfillment). In support of th...
Generality of support sources and psychometric properties of a scale of perceived social support in Turkey Eker, D; Arkar, H; Yaldiz, H (Springer Science and Business Media LLC, 2000-05-01) Pur-pose: The purpose of the study was to check the generality of the structure of social support sources as measured by the Multidimensional Scale of Perceived Social Support (MSPSS) and to examine the instrument's psychometric properties in Turkey. A previous study in Turkey showed that the definitions of support sources may differ across cultures and an attempt was made in the present study to incorporate definitions to make the scale more meaningful in Turkey. Method: Three samples (psychiatry, surgery,...
Collective Guilt Antecedets Outcomes and Ways of Avoding Sakallı, Nuray (2016-06-01) Bu makalenin amacı gruplar arası ilişkiler bağlamında diğer gruba zarar verme sonucunda bireylerin grup üyeliklerine bağlı olarak hissedebilecekleri kolektif suçluluk duyma ve bu duygudan kaçınmak için kullanılan stratejileri kapsayan çalışmaları derleyerek alana tanıtmaktır. Bu kapsamda öncelikle kolektif suçluluk duyma kavramı tanımlanmaktadır. Bu tanımlamada kolektif suçluluk duymaya alternatif olarak kullanılan bazı psikolojik süreçlere değinilmekte ve kolektif suçluluğun kişisel suçluluk ve kolektif ut...
Trust in principals Zayim Kurtay, Merve (Oxford University Press, 2020-09-01) Trust is generally considered as the basis of relationships between major school stakeholders and contributes not only to productive attitudes and behaviors but also to the accomplishment of collective goals. The principal is the key person in creating the atmosphere and the conditions conducive to trust in which trust-based relationships among school constituencies can flourish. Specifically, school culture characterized by collegiality, professionalism, and consideration generally leads to higher trust in...

Citation Formats

M. U. Demirci, “Explicit and implicit trust modeling compatibility and explicit trust link prediction in trust-based recommendation systems,” M.S. - Master of Science, Middle East Technical University, 2022.