methodatlas
Method guideKnowledge Modeling

Competency Questions

A practical method guide: clarify prerequisites and materials, understand the complete process, and look up outputs, pitfalls, and stop criteria.

ComplexityMedium
Time2-4 h
Participants2-8
FormatWorkshop + async
MaturityEstablished
Plan Competency Questions
01

Prerequisite

What needs to be finished first

Complete firstBounded subject

The scope and purpose of Competency Questions are stated as a concrete question.

Without scope, competency question test suite becomes arbitrary.
Complete firstAccess to relevant perspectives

Use cases and decision questions, domain vocabulary, representative instance data and domain decision makers are available.

Without these perspectives, central claims in competency question test suite remain unsupported.
02

Preparation

What needs to be ready before start

Materials

Use cases and decision questions, domain vocabulary, representative instance data, shared workspace, source links, and decision log.

People / roles

Domain expert · ontology engineer · data consumer

Pre-read

Collect Use cases and decision questions, domain vocabulary, representative instance data in advance and mark open assumptions.

Time needed

60–90 minutes initially; ongoing test maintenance

Setup

Prepare translate a natural-language domain question into terms, formal query, test data, and expected answer visibly and calibrate assessment terms before starting.

03

Core question

The one question this method answers

Which domain questions must the ontology answer with defined data and inferences?

04

Flow

Phases with goal, actions, output and pitfall

Competency questions state in natural language which inferences an ontology should enable. Terms, quantification, example answer, and test query are explicit.

competency question test suite

Fictional worked example

translate a natural-language domain question into terms, formal query, test data, and expected answer as a precise working structure with a fictional example.

Competency question

User · question · decision

Which open actions are overdue?

Semantics

Terms · quantifier · horizon

status=open; dueDate<today.

Test case

Data · expected answer · negative case

A-17; completed A-18 excluded.

Formalisation

Query · axioms · version

SPARQL + hasOwner/memberOf.

The example demonstrates the domain logic of Competency Questions; worksheets remain blank.

Grüninger and Fox: Methodology for the Design and Evaluation of Ontologies

  1. 1

    Elicit question

    Elicit question

    Goal

    Produce CQ backlog so the core question “Which domain questions must the ontology answer with defined data and inferences?” can be answered with stronger support.

    Inputs for this step

    • Use cases and decision questions
    • domain vocabulary
    • representative instance data

    Actions

    • Collect real decision questions with domain actors.
    • Record source, rationale, and open uncertainty directly in CQ backlog.

    Output

    CQ backlog

    CQ backlog · source · uncertainty · next decision

    Quality check

    Is the question relevant to a concrete user?

    Pitfall

    The domain question remains vague or has no unambiguous expected test answer. Clarify decision context, quantifier, horizon, and expected example answer before formalising.

    Timing: 10–20 minutes

  2. 2

    Specify

    Specify

    Goal

    Produce precise CQ so the core question “Which domain questions must the ontology answer with defined data and inferences?” can be answered with stronger support.

    Inputs for this step

    • CQ backlog
    • domain vocabulary
    • representative instance data

    Actions

    • Clarify quantifier, horizon, terms, and desired answer.
    • Record source, rationale, and open uncertainty directly in precise CQ.

    Output

    precise CQ

    precise CQ · source · uncertainty · next decision

    Quality check

    Can a unique example answer be given?

    Pitfall

    The domain question remains vague or has no unambiguous expected test answer. Clarify decision context, quantifier, horizon, and expected example answer before formalising.

    Timing: 10–20 minutes

  3. 3

    Formalise

    Formalise

    Goal

    Produce query test so the core question “Which domain questions must the ontology answer with defined data and inferences?” can be answered with stronger support.

    Inputs for this step

    • precise CQ
    • domain vocabulary
    • representative instance data

    Actions

    • Translate CQ into a query and required axioms.
    • Record source, rationale, and open uncertainty directly in query test.

    Output

    query test

    query test · source · uncertainty · next decision

    Quality check

    Does the formal query preserve the domain question?

    Pitfall

    The domain question remains vague or has no unambiguous expected test answer. Clarify decision context, quantifier, horizon, and expected example answer before formalising.

    Timing: 10–20 minutes

  4. 4

    CQ tests

    CQ tests

    Goal

    Produce CQ test suite so the core question “Which domain questions must the ontology answer with defined data and inferences?” can be answered with stronger support.

    Inputs for this step

    • query test
    • domain vocabulary
    • representative instance data

    Actions

    • Run positive, negative, and boundary test data.
    • Record source, rationale, and open uncertainty directly in CQ test suite.

    Output

    CQ test suite

    CQ test suite · source · uncertainty · next decision

    Quality check

    Does the test fail when a core axiom is missing?

    Pitfall

    The domain question remains vague or has no unambiguous expected test answer. Clarify decision context, quantifier, horizon, and expected example answer before formalising.

    Timing: 10–20 minutes

05

Artifact

What comes out at the end

Sketch: what the artifact looks like

Competency Questions · Questions as Model TestsTranslate domain questions into concepts, relationships, test queries, and coverage
Competency QuestionsDomain questions are decomposed into concepts and relationships, formulated as test queries, and checked against coverage.Constrain the ontology through answerable questionsEach domain question defines modeling needs and later becomes a test against the graph.derivetestCoverageCompetency Questionsconcrete domain questionsCQ1Which services depend on X?CQ2Who owns cluster Y?CQ3Which paths lead to risk Z?Model excerptderive concepts and relationshipsOWNSRUNS_ONServiceTeamClusterTest Querycheck against example graphMATCH Service-[:DEPENDS_ON]->RETURN path, ownerCoverage Matrixanswerable or gap?CQ1okCQ2okCQ3gap
Form

Versioned competency question test suite with date, sources, owners, and next review.

Versioning / ownership

Retain date, source, assumption state, and decision for every version of competency question test suite.

Tool alternatives
  • competency question test suite as board or document
  • Source and evidence register
  • Decision and action log

competency-questions-working-template.md

Plan Competency Questions around its domain steps and the concrete decision question.

Competency Questions: Worksheet

Question

To be confirmed

Desired outcome

To be confirmed

Scope

Full workshop Time: 60–90 minutes initially; ongoing test maintenance

Complete this worksheet on paper or in your own document during the work.

Preparation for this scope

Method setup

  • Materials: Use cases and decision questions, domain vocabulary, representative instance data, shared workspace, source links, and decision log.
  • Roles: Domain expert · ontology engineer · data consumer
  • Advance information: Collect Use cases and decision questions, domain vocabulary, representative instance data in advance and mark open assumptions.
  • Overall time needed: 60–90 minutes initially; ongoing test maintenance
  • Setup: Prepare translate a natural-language domain question into terms, formal query, test data, and expected answer visibly and calibrate assessment terms before starting.

Prepare for the work steps

Elicit question: Elicit question

  • Use cases and decision questions
  • domain vocabulary
  • representative instance data

Specify: Specify

  • CQ backlog
  • domain vocabulary
  • representative instance data

Formalise: Formalise

  • precise CQ
  • domain vocabulary
  • representative instance data

CQ tests: CQ tests

  • query test
  • domain vocabulary
  • representative instance data

competency question test suite

Competency question

User · question · decision

...

Semantics

Terms · quantifier · horizon

...

Test case

Data · expected answer · negative case

...

Formalisation

Query · axioms · version

...

Enter only real input, sources, and decisions.

Grüninger and Fox: Methodology for the Design and Evaluation of Ontologies

Elicit question: Elicit question

Expected artifact: CQ backlog

CQ backlog · source · uncertainty · next decision

Entry:

...

  • Is the question relevant to a concrete user?

Specify: Specify

Expected artifact: precise CQ

precise CQ · source · uncertainty · next decision

Entry:

...

  • Can a unique example answer be given?

Formalise: Formalise

Expected artifact: query test

query test · source · uncertainty · next decision

Entry:

...

  • Does the formal query preserve the domain question?

CQ tests: CQ tests

Expected artifact: CQ test suite

CQ test suite · source · uncertainty · next decision

Entry:

...

  • Does the test fail when a core axiom is missing?

Open questions and next steps

...

Method guide: https://methodatlas.meierhoff-systems.de/en/methods/competency-questions/run-sheet

06

Example output

Concrete filled scenario, fictional example

Fictional example for orientation. Counts and timings describe this case and are not universal requirements.

competency-questions-beispiel.md

Concrete filled scenario, fictional example

CQ: which open actions are overdue today, and which organisation contains their owner? Terms: Action, dueDate, status, hasOwner, memberOf. Test data contain two open and one completed action. Expected: A-17 only. The SPARQL test runs for every ontology version.

07

Pitfalls

Recognize symptoms and steer against them

Quick overview, the full text is in the matching phase in the flow

  1. Elicit questionThe domain question remains vague or has no unambiguous expected test answer.View in phase
  2. SpecifyThe domain question remains vague or has no unambiguous expected test answer.View in phase
  3. FormaliseThe domain question remains vague or has no unambiguous expected test answer.View in phase
  4. CQ testsThe domain question remains vague or has no unambiguous expected test answer.View in phase
08

Stop criteria

When to pause, resolve prerequisites, or choose another approach

competency question test suite answers the core question with traceable evidence or explicitly marked uncertainty.
Owners, next actions, and review dates are named for open points.

Finished the method guide?

Go to the profile for purpose, similar methods, and sources or continue to the next method in the catalog.