INFS3101/7100 Ontology and the Semantic Web

Exercises from Week 2

For discussion in tutorial week 3

Key concepts from lecture: Institutional fact is a record of a speech act. Brute fact X counts as institutional fact Y in context C. Context includes framing rules and background. Most information systems manage records of speech acts. Interoperating agents perform speech acts, both performative and informative.

1.           Consider the following examples of institutional facts. What are the corresponding brute facts? In what context does the brute fact count as the institutional fact (consider both framing rules and some of the background)? What is the speech act of which the institutional fact is a record, and who makes it?

a.           An Australian $1 coin

b.           Your drivers licence

c.           Your citizenship

d.           How you are legally able to reside here to study in this University

e.           A goal in soccer.

2.           (relevant to points 2 and 4 of the assignment) Consider a hypothetical exchange concerned with rental accommodation in a particular district.

People want to rent accommodation. They can either rent an entire unit/house, in which case they sign a lease for a fixed term, or rent a room in a unit/house leased by someone else for an indefinite term. In either case they undertake to pay rent and a share of expenses. Someone who signs a lease pays a bond. Someone who rents a room in a unit/house leased by someone else may or may not pay a bond. Some accommodation is furnished and some not. Some allow pets and some do not.

Owners of units or houses place them for rent with an estate agent, who manages the leases, looks after bonds and collects rent. The owners set the amount of rent. The exchange includes many estate agents.

A unit/house is described by type of building (unit or house), suburb, nearness to shops, rail, busses, ferry, whether furnished or not. A room is described by who else is in the house, whether furnished or not, dates available, and possibly gender/cultural background of person sought, dietary preferences, smoker/non-smoker, etc. 

a.           Identify three distinct players who interoperate using this ontology, and three distinct roles that can be taken in the interoperation. Briefly describe what each role does and how the players interact using the ontology. Show three concrete actions taken by players as they interoperate. Include details of players and roles involved, and the contents of the messages.   

b.           Describe three institutional facts created in this network, including brute fact and context. What roles are responsible for creation of each fact? Who is responsible for keeping the definitive record of the fact?

c.           Describe two performative and two informative speech acts performed in this system.