DOYLC

An involuntary hiatus has prevented me from the pleasure of blogging on definitions for about a month.  I am now gradually getting back to normal, and am able to blog again. Today I want to look at concept systems, and types of concept system. In data modeling, only one type of concept system commonly appears - the generic concept system, containing Supertypes and Subtypes.  Very occasionally, the part-whole type of concept system can also be found.  The latter be seen in "bill of material" structures.  Strangely, the visual representation of a generic concept system and a part-whole concept system can look very similar in a data model.   I think that this leads data modelers to play down the idea of concept systems, and indeed the term "concept system" is not really met with in data modeling. However, if we turn to the discipline of terminology, the idea of concept system is very prominent, and different types of concept systems are called out.  Let m...

Dave Hay commented on my post How Many Attributes Do I Have?   Dave notes that there is a difference between me and the roles that I play.  This is an important point that I struggled with previously.  Dave states "most of the examples are attributes of my role as a customer", meaning the examples I provided in my post. "Role" is a term that gets bandied around a lot in data modeling.  In my previous post on Role vs. Relationship I argued that roles really refer to certain kinds of relationships.  However, Dave's point is one that I have heard on a lot of occasions and has to be taken seriously. Let's state the question this way: is the attribute Customer Lifetime Value to Hardbitten Liquors an attribute of me, or an attribute of my role as a customer of Hardbitten Liquors?  And if the latter, just what do we mean by "role". There is no doubt that I am an instance of a concept.  The concept is human being.  Further, Customer Lifetime Value to Har...

Most of my experience in doing definition work has mostly been from the perspective of an analyst involved in systems development.  These days it usually data-centric applications, such as building Master Data Management (MDM) or business intelligence (BI) environments.  The method of the analyst begins with understanding scope and requirements, and then finding the business concepts and data objects that need to be defined. However, there are other perspectives.  Terminologists, often oriented to the language translation industry, do deinition work.  So, I suspect, do brand managers, who want to control messaging to customers. I work a good deal in financial services, and I am aware that there is another group that gets involved in definitions.  These are business people who create completely new products.  For instance, Asset Backed Securities (ABS) and Colladeralized Debt Obligations - both now notorious as weapons of mass financial desctruction - were c...

Charact eristics of a concept - its attributes - are central to definitions.  But to what extent should the characteristics of a concept be listed in its definition?  Should it be few, or some, or as many as possible?  As a step in beginning to answer that question, I think that we need to ask if we can reliably determine all the characteristics that a concept possesesses.  And I now intend to see if I can answer that question by finding out if I can list all the attributes that I possess. I am aware that I am an instance and not a concept (at least a general concept).  However, I would submit that there is a prima facie case that I should be able to provide a list of my attributes.   If such a list could be produced, then we couldn see if the attributes apply to the concept I am an instance of (humans).  We could then move on to figuring out what attributes should or should not be included in a definition.  But, if I cannot even r...

I wanted to return to the issue of Pluto, which has already been the subject of a number of posts.  The International Astronomical Union (IAU) created a rich array of issues and problems when it undertook a definitional change that resulted in the demotion of Pluto to the class of "dwarf planets". The topic this time is what exactly did the IAU define? I was watching a PBS special on the status of Pluto a few days ago.  It included scenes from a diner where the genial Neil deGrasse Tyson was asking customers what they thought about the new status of Pluto.  The reponses varied, but the issue at hand was about whether Pluto was "a planet".  The diners all thought that they were dealing with the general concept signfied by the term "planet".  Yet there is reason to think they were mistaken. The IAU resolved (see http://www.iau.org/public_press/news/detail/iau0603/ ) concerning the following: "The IAU therefore resolves that planets and other bodies in o...

Stijn commented on my earlier post "What is an Identifying Characteristic?" ( http://definitionsinsemantics.blogspot.com/2011/11/what-is-identifying-characteristic.html ) raising the point that "identification of a thing is dependent on the application".  He lists out things that identify him, and notes that one cannot always be substituted for another.  E.g. a passport cannot always be substituted for a driving license.  It depends on the application, and each application has rules about what can be used as identification.  Stijn asserts that trying to capture all such rules in a definition will create conflict between the parties representing the applications.  So he advises us to separate a definition from capturing such rules. There are a lot of topics compressed into this comment, so I am only going to pick one here.  It is the different classes of identification that should be captured in a definition.  I suggest that these are: Characteristics o...

A couple of days ago I was reading some material on a semantics product and came upon the term "role".  We see role used in data modeling where a primary key migrated into a child entity can be assigned a "role name".  This is the name by which the attribute is known in the child entity, and is useful to disambiguate the same attribute migrated for other relationships between the same two entities. You also hear about "role" in the party model.  Rather than say that Unindicted Broker is a client of Overleveraged Bank, and that Unindicted Broker is a prime broker for Overleveraged Bank, we can say that Unindicted Broker is a party that plays two roles with Overleveraged Bank: (a) client; and (b) prime broker. I think that there are deeper issues here.  We think of a relationship in a data model as a line between two entities.  We cannot allocate attributes to the relationship as we can to entities.  Our notations, methodologies, and tools will not allows it...