Models Flashcards
Fifth bundle
Difference between model and theory (Bohr model)
GENERAL:
- theories represent abstract/general features, models might also represent specific targets
- theories evaluated by their truth, models evaluated conditional on their purpose
BOHR THEORY:
1) One has reasons to believe that theory is not false
2) The object of the theory is governed by principles stated in theory
BOHR MODEL:
1) Provides approximation of object in question
2) Alternative representations of the same object useful for other purposes exist
Both theories and models represent parts of the target
Core uses of/when to use scientific models
Models are used because investigating the target directly would be:
- Physically impossible or too costly.
- Legally or morally prohibited.
- Cognitively too demanding, so that we instead investigate a simplified model.
isolating model
- single out one aspect of the target (ignoring all others)
- they represent the workings of that factor accurately
! what does it mean that a model is true
That it is an accurate representation
! Wright brothers example over how isolating models can be said to be true
true…..?? that it is accurate?
They didn’t create a flyable model right away, they began with isolating models like wind tunnels and smaller scale models of smaller components
Epistemic virtues for scientific models
precision, similarity, transparency, simplicity,
(these as well???)…predictability, explanatory power, closeness to truth, degree of fit with observations, coherence…
Why can scientific models only satisfy some epistemic virtues, but not all, at the same time?
Increasing one epistemic virtue in a model often means decreasing another one
similarity—–simplicity
precision—–transparency
Building a model means finding the trade-off best for your purpose!
What is the internal validity of a model?
When errors are avoided: correct proof, correct programming
I.V. less of a problem for models than for experiments
What is the external validity of a model?
When assumptions in the model are similar to properties of the target
(E.V. a problem for all models but only for some experiments)
! What is the “target” or “real world target” of a model?
The object of attention/focus