Add additional types of variables to repr.ttl

[lewismc]

Preferred term labels

Controlled Variable (http://sweetontology.net/repr/ControlledVariable) and Extraneous Variable http://sweetontology.net/repr/ExtraneousVariable

Synonyms

n/a

Textual definition

A controlled variable or constant variable is a variable that does not change during an experiment.
Example: In the experiment measuring the effect of temperature on solubility, controlled variable could include the source of water used in the experiment, the size and type of containers used to mix chemicals, and the amount of mixing time allowed for each solution.

Extraneous variables are "extra" variables that may influence the outcome of an experiment but aren't taken into account during measurement. Ideally, these variables won't impact the final conclusion drawn by the experiment, but they may introduce error into scientific results. Examples of extraneous variables include accidents, factors you either can't control or can't measure or factors you consider unimportant. Every experiment has extraneous variables.
Example: You are conducting an experiment to see which paper airplane design flies longest. You may consider the color of the paper to be an extraneous variable. You note in your lab book that different colors of papers were used. Ideally, this variable does not affect your outcome.

Suggested parent term

http://sweetontology.net/reprMath/Variable

Other information

I am honestly a bit confused about how to differentiate http://sweetontology.net/reprMath/Variable and http://sweetontology.net/humanResearch/Variable. The former is a rdfs:subClassOf math:NumericalEntity and the latter rdfs:subClassOf repr:Representation however the former contains sub classes whilst the latter does not. I'll submit a PR and we can

Attribution

https://orcid.org/0000-0003-2185-928X