This is one of the possible Use Cases.
1. Abstract
A couple of friends want to spend their vacation together and use a Web-based travel service for recommending restaurants and out of ordinary places and for making the necessary travel arrangements. For this purposes, the travel service uses the profiles of the persons taking part at the trip.
2. Status
The use case has been proposed by REWERSE to the RIF WG participants as use case 'Rule-based personalization: Organizing a vacation with friends'.
3. Links to Related Use Cases
Part of persons' profiles in the use case described here could be specified as in Ben's personal interests, friends, etc. in use case RIF RuleML FOAF.
4. Relationship to OWL/RDF Compatibility
5. Examples of Rule Platforms Supporting this Use Case
6. Benefits of Interchange
Benefit 1: Data and rules making up the persons' profiles need to be interchanged between systems (e.g. travel service and more specialized services such as hotel booking services).
Benefit 2: Data and rules of different profiles need to be combined so as to find a trip fitting most of the persons' expectations. Also, it might be the case that the travel service's business rules (e.g. for offering discounts) need to be also considered in the process of arranging a trip.
7. Requirements on the RIF
- Different kinds of rules (deductive, normative, and reactive rules) should be supported.
8. Breakdown
8.1. Actors and their Goals
- Group of friends, each person having its own profile.
- Travel service plans trips by combining different services and using the profiles of the persons taking part at the trips.
8.2. Main Sequence
9. Narratives
A couple of friends living now in different European countries want to spend their vacation together. They use a Web-based travel service for recommending restaurants and out of ordinary places and for making the necessary travel arrangements. The service combines a couple of specific services, for example hotel reservation services and transportation services.
Each friend has its own (personalized) profile, that is a set of rules defining the person's likes and dislikes, interests, constraints (such as time and finances), etc. and data about previously made trips, hotels' rating, etc. Profiles are the result of monitoring activities (e.g. visiting online museums or buying books online), filling in online registration forms, dialogue with travel office employees, or combinations of these. Of course, the group of friends authorized the travel service to use and share their profiles.
So as to arrange a trip and make recommendations that suit (most of) friends' expectations and constraints, the travel service needs to 'combine' the profiles of the persons taking part at the trip. Rules regarding particular issues (such as dietary requirements or activities of interest) are to be interchanged between services making the corresponding booking of and/or recommendations for the trip. Moreover, each such service has its own rules for determining suitable proposals and recommendations for the planned travel.
10. Commentary
The following rules and data exemplify part of George's profile that is used by the travel service:
(1) George prefers cheap restaurants, but no Indian ones.
(2) George prefers to travel away from expensive, over-developed resort areas.
(3) George prefers locations full of history.
(4) George visited the following places: ... .
The travel service uses deductive rules for inferring data on-demand. For example statement (3) could be inferred based on the places George has visited before by using a rule such as
(5) IF Person visited at least three locations full of history THEN Person prefers locations full of history
For determining the locations full of history, views (specified by deductive rules) over a city and region database are used. For example, such a view could contain Rome and Athens as locations full of history.
Normative rules (or integrity constraints) are used for example for posing constraints regarding dietary requirements or finances:
(6) IF restaurant R is recommended for person P THEN R has vegetable dishes OR R has fish dishes
Reactive rules are used for monitoring activities (e.g. visiting online museums or buying books online) and updating profiles:
(7) IF person P orders online a tennis racket THEN add tennis to P's activities of interest