Difference between revisions of "Variable"

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<section begin=glossary />
 
<section begin=glossary />
 
:'''Variable''' is a description of a particular piece of reality. It can be a description of a physical phenomenon, or a description of value judgements. Also decisions included in an assessment are described as variables. Variables are continuously existing descriptions of reality, which develop in time as knowledge about them increases. Variables are therefore not tied into any single assessment, but instead can be included in other assessments. A variable is the basic building block of describing reality.<section end=glossary />
 
:'''Variable''' is a description of a particular piece of reality. It can be a description of a physical phenomenon, or a description of value judgements. Also decisions included in an assessment are described as variables. Variables are continuously existing descriptions of reality, which develop in time as knowledge about them increases. Variables are therefore not tied into any single assessment, but instead can be included in other assessments. A variable is the basic building block of describing reality.<section end=glossary />
 +
 +
==Variable Structure==
 +
 +
;The structure of a variable is such that it:
 +
:* is able to systematically handle all kinds of information about the particular piece of reality that the variable is describing,
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:* is able to systematically describe causal relationships between variables,
 +
:* enables both quantitative and qualitative descriptions,
 +
:* is suitable for any kinds of variables, especially physical phenomena, decisions, and value judgements,
 +
:* inherits its main structure from [[universal object]]s,
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:* complies with the [[PSSP]] ontology,
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:* can be operationalised in a computational model system,
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:* results in variables that are independent of the assessment(s) it belongs to;
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:* results in variables that pass the [[Plausibility test|clairvoyant test]].
 +
 +
'''In practice, it is formed according to the following table.'''
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 +
{|{{prettytable}}
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|+Table 3. The attributes of a variable.
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! [[Attribute]]
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! Sub-attribute
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! Comments specfic to the variable attributes
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|-----
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| '''Name'''
 +
|
 +
|
 +
|-----
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| '''Question'''
 +
|
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| This includes a question from the viewpoint of the user, such that serves the users purposes.
 +
|-----
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| '''Answer'''
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|
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| An answer presents an understandable answer to the question. It is preferably a probability distribution (which can in a special case be a single number), but an answer can also be non-numerical such as "very valuable". The units of interconnected variables need to be coherent with each other given the functions describing causal relations. The units of variables can be used to check the coherence of the causal network description. This is a so called [[Plausibility test|unit test]].
 +
|-----
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| rowspan="4" | '''Rationale'''
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| Rationale
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| Rationale gives credibility to the answer in the eyes of a critical reader. It presents the reader the information required to derive the answer and explains how it is formed.
 +
|----
 +
| Dependencies
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| Dependencies {{reslink|Dependencies instead of causality}} tells what we know about how upstream variables (i.e. causal parents) affect the variable. Dependencies list the causal parents and expresses their functional relationships (the variable as a function of its parents) or probabilistic relationships (conditional probability of the variable given its parents).
 +
|----
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| Formula
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| Formula {{reslink|Discussion on formula attribute}} is an operationalisation of how to calculate or derive the result. Formula uses algebra, computer code, or other explicit methods if possible.
 +
|----
 +
|}
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 +
In addition, it is practical to have additional subtitles on a variable page. These are not attributes, though.
 +
* See also
 +
* References
  
 
==See also==
 
==See also==
  
 
* [[:Category:Variables | List of all variables]] in Opasnet
 
* [[:Category:Variables | List of all variables]] in Opasnet
−
* [[Variable structure]]
 
 
* [[Universal object]]
 
* [[Universal object]]
 
* [[Open assessment]]
 
* [[Open assessment]]

Revision as of 09:46, 7 June 2012


<section begin=glossary />

Variable is a description of a particular piece of reality. It can be a description of a physical phenomenon, or a description of value judgements. Also decisions included in an assessment are described as variables. Variables are continuously existing descriptions of reality, which develop in time as knowledge about them increases. Variables are therefore not tied into any single assessment, but instead can be included in other assessments. A variable is the basic building block of describing reality.<section end=glossary />

Variable Structure

The structure of a variable is such that it
  • is able to systematically handle all kinds of information about the particular piece of reality that the variable is describing,
  • is able to systematically describe causal relationships between variables,
  • enables both quantitative and qualitative descriptions,
  • is suitable for any kinds of variables, especially physical phenomena, decisions, and value judgements,
  • inherits its main structure from universal objects,
  • complies with the PSSP ontology,
  • can be operationalised in a computational model system,
  • results in variables that are independent of the assessment(s) it belongs to;
  • results in variables that pass the clairvoyant test.

In practice, it is formed according to the following table.

Table 3. The attributes of a variable.
Attribute Sub-attribute Comments specfic to the variable attributes
Name
Question This includes a question from the viewpoint of the user, such that serves the users purposes.
Answer An answer presents an understandable answer to the question. It is preferably a probability distribution (which can in a special case be a single number), but an answer can also be non-numerical such as "very valuable". The units of interconnected variables need to be coherent with each other given the functions describing causal relations. The units of variables can be used to check the coherence of the causal network description. This is a so called unit test.
Rationale Rationale Rationale gives credibility to the answer in the eyes of a critical reader. It presents the reader the information required to derive the answer and explains how it is formed.
Dependencies Dependencies R↻ tells what we know about how upstream variables (i.e. causal parents) affect the variable. Dependencies list the causal parents and expresses their functional relationships (the variable as a function of its parents) or probabilistic relationships (conditional probability of the variable given its parents).
Formula Formula R↻ is an operationalisation of how to calculate or derive the result. Formula uses algebra, computer code, or other explicit methods if possible.

In addition, it is practical to have additional subtitles on a variable page. These are not attributes, though.

  • See also
  • References

See also

References

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