64 lines
2.3 KiB
Markdown
64 lines
2.3 KiB
Markdown
---
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aliases:
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- rule-of-thumb
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title: Heuristics
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tags:
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- type/encyclopedia
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---
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# Heuristics
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A heuristic, or "rule of thumb", is a solution
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that neglects some of a problem's complexity,
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while still producing a satisfactory result.
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The namesake rule of the rule of thumb
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is that the width of one's thumb is about an inch.
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With that heuristic,
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one can closely approximate small dimensions,
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even without the proper tools.
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It is tempting to believe that heuristics are not ideal,
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that the most accurate method ought to be preferred,
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but the most accurate method is rarely practical.
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Afterall, even using a ruler is a heuristic,
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subject to the tool's tolerance
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and reliant on its proper use.
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The suitability of a model
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is dependent on the purpose of the measurement.
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To determine the width of dimensional lumber,
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for example, to determine if a board is a 2x4 or a 2x6,
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the rule of thumb is perfectly suitable,
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and a micrometer would be silly.
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> [!quote] George E. P. Box, British statistician
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> All models are wrong, but some are useful.[^1]
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[^1]: > [!quote] [[box-et-al_1987_empirical-model-building#The Use of Approximating Functions]]
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> The fact that the polynomial is an approximation
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> does not necessarily detract from its usefulness
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> because all models are approximations.
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> Essentially, all models are wrong, but some are useful.
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## Realism vs. Instrumentalism
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Realism holds that the purpose of [scientific research](https://en.wikipedia.org/wiki/Research)
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is to describe the world as accurately as possible.
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Instrumentalism (anti-realism) argues that the purpose
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is to _forecast as accurately as possible_.
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> [!quote] _Opinionated History of Mathematics_, "Did Copernicus steal ideas from Islamic astronomers?" (pp.)
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> Ptolemy's lunar model is "flawed"
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> in that it inaccurately describes Luna's distance from Earth,
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> however Ptolemy only ever used the model to predict eclipses,
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> which the model does very well.
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> The discrepancy is only a flaw from a realist perspective.
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Realism is noble, granted,
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but instrumentalism is far more practical.
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## See Also
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* [Map--territory relation - Wikipedia](https://en.wikipedia.org/wiki/Map%E2%80%93territory_relation)
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* "Mistaking the map for the territory" (logical fallacy)
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* [Bonini's paradox](https://en.wikipedia.org/wiki/Bonini%27s_paradox) |