1 / 15

Chapter 20: Social Service Selection

Chapter 20: Social Service Selection. Service-Oriented Computing: Semantics, Processes, Agents – Munindar P. Singh and Michael N. Huhns, Wiley, 2005. Reputation Mechanisms. The agency (e.g., eBay) is the authority that Authenticates users Records, aggregates, and reveals ratings

Download Presentation

Chapter 20: Social Service Selection

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Chapter 20:Social Service Selection Service-Oriented Computing: Semantics, Processes, Agents– Munindar P. Singh and Michael N. Huhns, Wiley, 2005

  2. Reputation Mechanisms The agency (e.g., eBay) is the authority that • Authenticates users • Records, aggregates, and reveals ratings • Provides the conceptual schema for • How to capture ratings (typically a number and text) • How to aggregate them • How to decay them over time • Owns ratings – controls how it can be used Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  3. Recommender Techniques • Content-based filtering • Social information filtering • Collaborative filtering • Model-based approaches • Memory-based approaches • Use ratings directly to recommend Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  4. Recommending Products vs. Services • Products (by a product vendor) • The recommender is the provider • Votes are known to recommender • Votes are given prior to usage (buying) • Repetition is less likely (buy the same book) • Services (by a service registry) • The recommender is not the provider • Votes are not necessarily known to recommender • Votes are given after usage • Repetition can occur but not known to registry Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  5. Referrals

  6. Social Networks and Referral Chains • Referral chains provide: • Way to judge the quality of an expert's advice • Reason for the expert to respond in a trustworthy manner Social networks induce referral chains in which an individual may participate • As the chains get longer • The trustworthiness of a recommendation decreases • The effort to find experts increases • Therefore, shorter chains are better Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  7. Service Communities • Each principal • Provides services to others • Exploits services provided by others • Has a reputation • The agents assist their users and other agents in • Evaluating the services and referrals provided by others • Maintaining contact lists • Deciding whom to contact for a service Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  8. Distributed Treatment of Referrals Receive request Ask Model asker Follow referrals Respond Use Rate; update Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  9. Model for Referrals • Each agent has • An interest (services sought) • An expertise (services provided) • Models of acquaintances • Acquaintance models are built autonomously and represent • Acquaintances’ expertise (ability to provide good service along a set of dimensions) • Sociability (ability to provide accurate referrals) Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  10. Reputation Buildup and Collapse A participant who begins to misbehave is detected Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  11. Social Mechanism for trust

  12. Small World Phenomenon Milgram (1967): two individuals chosen at random in the U.S.A. are linked by a chain of 6 or fewer first-name acquaintances (empirical observation) • Six degrees of separation • Erdös numbers • Diameter of the connected Web: 20 Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  13. Social Mechanism of trust • Using probabilistic models for reasoning with beliefs • Bayesian model • Primarily using conditional probabilities • Dempster-Shafer model • Model that explicitly deals with belief values for various hypothesis Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  14. Identity & Reputation • Approaches to service selections based on reputations – face the threat that such reputations can be forged • Also, vendors can change names easily – “cheap pseudonyms” Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

  15. Highlights of this Chapter • Reputation Mechanisms • Recommender Techniques • Referrals • Social Mechanism for Trust • Identity Service-Oriented Computing: Semantics, Processes, Agents - Munindar Singh and Michael Huhns

More Related