Overview

This time we are focusing on the step before we can actually start to formalise our knowledge, i.e. to specify what we should actually formalise. In some cases you are building an ontology based on an existing dataset, then of course you would be looking at that dataset to figure out what to put into your ontology (at least in terms of classes and properties). However, many times you may instead start from interviewing a domain expert, or reading some documents that contain the kind of information you want to represent. In these cases it is useful to work with these kind of texts in a structured way, and try to elicit a set of requirements from them. Of course, in a realistic scenario you probably need more than the texts to figure out all the details, and you then need to verify what you elicited with you 'customer' or a domain expert. However, in this case, we'll use just the text as a source of requirements.

Exercise

In this hands-on, you will start from a description of the purpose of the ontology and the projet you should imagine you are working on (named "context" below), and a text describing some typical information that should be managed by the system. The text has been broken down into smaller parts for you convenience. Your task is to take each such sub-part of the text and 1) generalise it, i.e. turn it into what we call 'instance-free sentences', and then 2) write potential Competency Questions (CQs), additional restrictions, and potential reasoning requirements that could be elicited from there. CQs are usually pretty obvious from the text itself, for the other two categories you may have to use a bit more imagination, since they would usually be written in a dialogue with the customer/domain expert.

Context

Tourist information about cities: A company providing a tourism web portal would like to semantically represent all their information about cities in Europe. Following is a typical description of the kind of information that is present in the portal, and that should be contained in (and queried from) the knowledge base.

Example of information that the system should manage

Rome is the capital of Italy, it is located in the Lazio region. Rome has two airports. Fiumincino airport is served by Alitalia flights, while Ciampino is served by Ryanair and Wizzair. Rome has several train stations, the main station is Termini located in the center of Rome, but there are also the Trastevere station in the west part of Rome (the Trastevere district), and Tiburtina in the south east. When getting around in Rome by public transport there are buses, trams and a metro with two lines (A and B). The metro lines A and B run until 00.30, and resume at 5.30 in the morning. In Rome you can stay in a hotel. Hotels have different ratings (from five to one star), and rates within a price range. Price ranges of the hotels differ depending on the time of the year that you decide to visit Rome.

Rome is full of sights, such as churches, monuments and museums. Popular churches are St Peters and the Pantheon, and a monument is the Colosseum. To enter the Colosseum there is a fee of 12 EUR for adults, a fee of 7,50 EUR for EU citizens below the age of 24 and free entrance for EU citizens below 18 years old. There are organised tours to see the sights of Rome, either on foot starting from the Pantheon or by bus leaving from the Termini station, with different starting times on different weekdays. Rome also has numerous museums. Museums are generally closed on Mondays, but the Vatican Museums are instead closed on Sundays.

While in Rome a visitor should take the opportunity to visit one of the many events taking place there during different periods, such as theater and opera performances, and concerts. During September and October 2009 the Teatro Roma offers two theater shows each evening. The play in this period is the "Merchant of Venice", written by Shakespeare in 1598, given through an ensemble of well-known actors. During the second and third week of September the role of Shylock is played by Arnold Schwarzenegger as a special guest actor.

There are a number of travel guides available for Rome, many of them are available in several formats, for example as a guidebook or on a CD. Maps of Rome can also be found in paper format or in an electronic format.

Problem divided into sub-parts, "requirement stories"

• Rome is the capital of Italy, it is located in the Lazio region.
• Rome has two airports. Fiumincino airport is served by Alitalia flights, while Ciampino is served by Ryanair and Wizzair. Rome has several train stations, the main station is Termini located in the center of Rome, but there are also the Trastevere station in the west part of Rome (the Trastevere district), and Tiburtina in the south east.
• When getting around in Rome by public transport there are buses, trams and a metro with two lines (A and B). The metro lines A and B run until 00.30, and resume at 5.30 in the morning.
• In Rome you can stay in a hotel. Hotels have different ratings (from five to one star), and rates within a price range. Price ranges of the hotels differ depending on the time of the year that you decide to visit Rome.
• Rome is full of sights, such as churches, monuments and museums. Popular churches are St Peters and the Pantheon, and a monument is the Colosseum. To enter the Colosseum there is a fee of 12 EUR for adults, a fee of 7,50 EUR for EU citizens below the age of 24 and free entrance for EU citizens below 18 years old.
• There are organised tours to see the sights of Rome, either on foot starting from the Pantheon or by bus leaving from the Termini station, with different starting times on different weekdays.
• Rome also has numerous museums. Museums are generally closed on Mondays, but the Vatican Museums are instead closed on Sundays.
• While in Rome a visitor should take the opportunity to visit one of the many events taking place there during different periods, such as theater and opera performances, and concerts. During September and October 2009 the Teatro Roma offers two theater shows each evening.
• The play in this period is the "Merchant of Venice", written by Shakespeare in 1598, given through an ensemble of well-known actors. During the second and third week of September the role of Shylock is played by Arnold Schwarzenegger as a special guest actor.
• There are a number of travel guides available for Rome, many of them are available in several formats, for example as a guidebook or on a CD. Maps of Rome can also be found in paper format or in an electronic format.