Questions and Answers About the Exam

This page will be used to answer questions about the spring 2020 exam.

Exam Questions as PDF

You can find the whole question set as a single PDF here

Section 1: RDF, OTTR

Question: Are we allowed to use templates from the OTTR library in the exam?

Answer: yes. It should be easy to solve the questions without the library, but if you find something useful there, feel free to use it.

Section 2: SPARQL

Question: Is there a way to test my query against those triples?

Answer: You can copy and paste the example triples from here into a file and then run Fuseki with that.  You can also use the SPARQL editor here  with the SPARQL endpoint https://sws.ifi.uio.no/fuseki/in3060v20/query (Put that in the text field above the query, next to the cogwheel) — but there is no guarantee that this service will be up and running at all times.  Remember that many students may be using it.

Section 3: RDFS Inference

Question: Regarding exercise 3d. There are no triples about :_x and :_y in the set. Are these supposed to be blank nodes, like _:x and _:y?

Answer: Yes, this is a typo. These are, as you say, supposed to be blank nodes and it should have been _:x and _:y.

Question: Are these to be solved the same way as the mandatory assignments?

Answer: Yes. The purpose is to use the RDFS entailment rules and the simple entailment rules. The RDFS entailment rules are here: (https://www.w3.org/TR/rdf-mt/#RDFSRules) and the simple entailment here: (https://www.w3.org/TR/rdf-mt/#simpleRules) (and on the lecture slides).

Question: In exercise 3g (Disjointnes). Can we only use the RDFS/RDF vocabulary, or can we use OWL as well?

Answer: The exercise explicitly asks for RDFS. You are not supposed to use OWL vocabulary in this exercise.

Section 4: Description Logic, OWL

Question? The information page it is said that we need to only use properties and classes from information page but in question no. 4g it is said to write DL axiom w.r.t budget and we don’t have any property or class of budget so can we use Budget Class or hasBudget property?

Answer: Yes, there is a typo here. There should indeed be a data property hasBudget that you can use to solve this exercise.

Question: Should there be a new property "hasBudget" or a class "Budget"?

Answer: Only a datatype property. No class.

Question: While solving for DL semantics, can we assume that "types" (for example, transitive, inverse, etc.) of some Properties exist? Otherwise, it seems that a few of the statements may not be expressed.

Answer: As long as your assumptions are reasonable, you should be fine. If you need to make assumptions to solve an exercise, it is usually a good idea to make them explicit.

Question: Nothing explicit is said about how a project manager is related to a project. Can we assume that isResponsibleForProject has domain ProjectManager and range Project?

Answer: isResponsibleForProject is the relation that connects a project manager to a project. If you need further assumptions, you can make them explicit. As long as the assumptions are reasonable, you should be fine.

Section 5: RDF and OWL Semantics, SHACL

Question: is it ok to write the triples as abbreviations, like r(i1, i2)

Answer: You may write the triples in the abbreviated style or in turtle style, whatever you find most convenient.

Question: Is it also required that we explain how the OWL axiom and the constraint mean different things?

Answer: An explanation of the difference between the OWL axiom and the constraint won’t hurt.  But it is sufficient to give the interpretations and triples as required by the questions.

 

Published June 5, 2020 12:40 PM - Last modified June 11, 2020 11:50 AM