SACM 1.0b2 FTF Avatar
  1. OMG Issue

SACM — Argument metamodel needs improvement

  • Key: SACM-167
  • Legacy Issue Number: 17347
  • Status: closed  
  • Source: Adelard LLP ( Luke Emmet)
  • Summary:

    The argument metamodel has some limitations that should be addressed to
    make it more coherent and simple. The following aspects need to be

    1. The annotation class is generally useful and should be promoted up
    the class diagram so it can be used more widely

    2. AssertedRelationships seem to be kinds of assertions (see related
    issue 16848) and so a number of related modelling updates will be needed
    to reorganise the model to reflect this, and to simplify by removing or
    renaming some of the abstract classes. An abstract Assertion class could
    be a useful common parent for both Claim and AssertedRelationship
    Classes. A simplification can be made then to rename the existing
    ArgumentLink as AssertedRelationship.

    3. We should have a simple referencing mechanism to allow referencing
    evidence in the evidence metamodel, or to reference other evidence by
    means of a URL directly (for when the user is only choosing to comply
    with the Argument compliance point)

    4. As the models are integrated it will be necessary to rename the top
    level element in ARM to be less generic

    I propose the following changes:

    Create a new Assertion class, as a subclass of ReasoningElement

    Set the Claim class to be a subclass of Assertion

    Rename the ArgumentLink abstract to be AssertedRelationship (removing
    the previous abstract class AssertedRelationship) and move the new
    AssertedRelationship class to be a child of the Assertion class

    Move the Annotation Class to a shared top level ModelElement, and
    include a content:String attribute

    Add an optional association from InformationElement to
    Evidence::EvidenceItem and add an attribute URL to InformationElement to
    be used to refer to evidence not held in the evidence model.

    Rename the ModelElement to be ArgumentationElement, and move the
    id:String attribute to its new parent ModelElement, which is part of the
    shared classes for the argumentation and evidence parts of SACM.

  • Reported: SACM 1.0b1 — Tue, 1 May 2012 04:00 GMT
  • Disposition: Resolved — SACM 1.0b2
  • Disposition Summary:

    Rename 9.2.1 to “ArgumentationElement class (Abstract)”
    Delete paragraph 1 of 9.2.1 and replace with:
    “An ArgumentationElement is the top level element of the hierarchy for argumentation
    In the Attributes section:
    delete the “identifier: String” attribute
    delete the text under “description: String”, and replace with “A description of the
    Argumentation entity”
    delete the text under “content: String”, and replace with “Supporting content for the
    Argumentation entity”
    delete the “Associations” heading and its content
    change the text of the “Semantics” section to be “The ArgumentationElement is a
    common class for all elements within a structured argument”
    delete the Invariants section
    Delete all of section 9.2.18 (Annotates Class)
    Delete all of Section 9.2.5 (ArgumentLink Class (Abstract))
    Insert a new Section 9.2.5 as follows:
    “Assertion Class (Abstract)
    Assertions are used to record the propositions of Argumentation (including both the
    Claims about the subject of the argument and structure of the Argumentation being
    asserted). Propositions can be true or false, but cannot be true and false simultaneously.
    Structured arguments are declared by stating claims, citing evidence and contextual
    information, and asserting how these elements relate to each other.

    Edit section 9.2.6 ReasoningElement Class (Abstract) as follows: First sentence, change “namely Claims and ArgumentReasoning” to “Assertions and
    Delete Attributes section and its content.
    Delete the content of the “semantics” section, and replace with “The core of any
    argument is the reasoning that exists to connect assertions of that argument. Reasoning is
    captured in SACM through the linking of fundamental claims and the description of the
    relationships between the claims. ReasoningElements represent these two elements.”
    Edit section 9.2.7 InformationElement Class as follows:
    Add an “attributes” section with the following content:
    url : string
    An attribute recording a URL to external evidence
    Add a new sentence at the end of the Semantics section as follows:
    “The url attribute is only to be used when only the argumentation aspects of SACM are
    complied with. If compliance is claimed against both the argumentation and evidence
    packages, then an association to Evidence::EvidenceItem shall be used to reference
    evidence by means of a URL”
    Add an "associations:" section with the following content:
    The EvidenceItems referenced by the current InformationElement object.
    Edit Section 9.2.9 Claim Class as follows
    Superclass section > Delete “ReasoningElement”, insert “Assertion” Attributes section>
    add “toBeSupported: Boolean An attribute recording whether further reasoning has yet to
    be provided to support the Claim (e.g. further evidence to be cited).”
    Semantics section, first para -> Delete first sentence (begins “Structured arguments are
    Semantics section, 2nd para-> delete “reasoning (in the recorded Argument)”, insert
    Semantics section: add 3rd para: “A Claim that is intentionally declared as requiring
    further evidence or argumentation can be denoted by setting toBeSupported to be true. “
    Add new “Invariant” Section with the content “Self.assumed and self.toBeSupported
    cannot both be true simultaneously”
    Edit 9.2.12 AssertedRelationship Class (Abstract) as follows
    Superclass section -> delete “ArgumentLink”, insert “Assertion”
    Insert new “Associations” section after “Superclass” section, with the following content:
    source:ArgumentElement[0..*] Reference to the ArgumentElement(s) that are the
    source (start-point) of the relationship.
    target:ArgumentElement[0..*] Reference to the ArgumentElement(s) that are the
    target (end-point) of the relationship.
    Semantics section, delete first sentence, replace with “In SACM, the structure of an
    argument is declared through the linking together of primitive ArgumentElements.”
    Edit section 9.2.13 AssertedInferenceClass as follows:
    Delete first para, replace with “The AssertedInference association class records the
    inference that a user declares to exist between one or more Assertion (premises) and another Assertion (conclusion). An assertion may be the target in more than one
    AssertedInference. It is important to note that such a declaration is itself an assertion on
    behalf of the user.”
    Semantics section, delete existing content, replace with “The core structure of an
    argument is declared through the inferences that are asserted to exist between Assertions
    (e.g. Claims). For example, an AssertedInference can be said to exist between two claims
    (“Claim A implies Claim B”). An AssertedInference between two claims (A – the source
    – and B – the target) denotes that the truth of Claim A is said to infer the truth of Claim
    Change title of 9.1 from 'Overview' into 'Argumentation Class Diagram'
    Replace Figure 9.1 with the following new figure <<figure on p 125 of ptc/2012-06-04>>

  • Updated: Fri, 6 Mar 2015 20:58 GMT