Names and Labels

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Name and Label: Discussion
Dan Gillman
Problem
• In general use, Name and Label are synonyms
• In DDI, usage guidelines are imprecise
• There exists theory to meaningfully differentiate them
• However, it means different usages of current terms
• Following theory can be used to close this gap
• Clear meanings and usage of all terms are laid out
• Terms “designation” and “definition” distinguished
Initial Definitions
• Object
• Definition: anything perceivable or conceivable
• Examples
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Any physical thing is a perceivable object
So is something detectable, such as light, voltage, or gust of wind
Abstract things, such as polygons or laws, are conceivable objects
Imagined things, such as unicorns, are also conceivable objects
• Concept
• Definition: unit of thought
• Special class of conceivable objects
Initial Definitions
• Examples
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The idea of an apple, as opposed to a particular one
Same for any class of physical objects
Numbers (not the numerals used to represent them)
The idea of unicorns
• Extension (of Concepts)
• Definition: the totality of objects to which a concept corresponds
• A particular apple is in the extension of the concept apple
• General Concept (example: planet)
• Definition: concept whose extension does not have exactly one object
Initial Definitions
• Individual Concept (example: Saturn)
• Definition: concept whose extension has exactly one object
• Individual concepts can be hard to understand
• Think of me, Dan Gillman
• That thought is the concept of me
• This concept is individual – there is one object in its extension
Caveat
• The terms “sign” and “signifier” in this document are synonyms
Label
• Label
• Definition: representation of an object by a sign which denotes it
• Model -
Label
• A label is a handle by which to refer to some object
• Synonym for Label
• Name – commonly used in database parlance
• Can mean either an identifier or just some moniker
• Kinds of Labels: Identifier, Locator, Designation
• Identifier
• Definition: label intended as a means to dereference the labelled object
• Locator
• Definition: identifier with known dereferencing scheme
Label
• Designation - Label for concepts
• Definition: representation of a concept by a sign which denotes it
• Since a concept is a kind of object, then a designation is a kind of label
• Model -
Designation
• Similar usage as words in natural language
• Denote meanings
• Used in communication
• If similar to NL words, then can convey some meaning
• Has kinds: term, appellation, code, and symbol
• Term
• Definition: linguistic designation for general concept
Designation
• Appellation
• Definition: linguistic designation for individual concept
• Synonym: Name
• “Name” now has 2nd use – Shouldn’t be used
• Examples are names of people
• Code
• Definition: non-linguistic designation, but denoted by alpha-numeric string
• Examples – consider categories in US Standard Occupational Classification (SOC)
• Codes are non-linguistic and denoted by strings
• 15-2011 is a code
• So-called “labels” are terms, which are linguistic and denoted by strings
• Airline Pilots, Copilots, and Flight Engineers is a term (commonly called a label)
Designation
• Symbol
• Any other designation
• For example – road signs, the meanings are understandable without words
Sign
• Used to denote objects
• Commonly, alpha-numeric strings
• But can be other things
• Example
• Number – a concept
• Numeral – sign, usually used to designate a number
• Signs
5, 5, 5 all designate the number five
• Each is perceivable object
• Actually, Sign is concept with extension limited to perceivable objects
Definitions
• Definition – natural language statement of the meaning of a concept
• Review definitions above
• Each starts with a previously defined concept then provides differentia
• These are intensional definitions
• An extensional definition delineates kinds:
• Example – Human teeth are incisors, canines, bicuspids, and molar
Definitions
• Difference between terms and definitions
• Terms are not necessarily statements
• Terms do not necessarily convey meaning, or at least not precisely
• Example –
• Unemployment as used by US Bureau of Labor Statistics
• Unemployment has English meaning, i.e., not employed
• Not the same as BLS meaning
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