All models are wrong, but some are useful.
This is a reference to mathematical models.
Remember that all models are wrong; the practical question is how wrong do they have to be to not be useful.
The markets were run by mathematicians and their models but they had no business sense.
[In science any model depends on a pre-chosen taxonomy] a set of classifications into which we divide the enormous complexity of the real world... Land, labor, and capital are extremely heterogeneous aggregates, not much better than earth, air, fire, and water.
You can build a statistical model and that's all well and good, but if you're dealing with a new type of financial instrument, for example, or a new type of situation - then the choices you're making are pretty arbitrary in a lot of respects.
Climate ... models bear about as much relation to reality as astrology.
We think that computer models represent reality especially if we developed the models.
It's a pretty widely-accepted notion that the atmosphere is a ridiculously complex system, and the best we can do with our models is a rough approximation.
The third-person or 'objective,' static, reductive models used in most science are important and yield significant results, but they have their limitations.
If you just rely on one model, you tend to amputate reality to make it fit your model.
Computer models of the climate....[are] a very dubious business if you don't have good inputs.
For far too long economists have sought to define themselves in terms of their supposedly scientific methods. In fact, those methods rely on an immoderate use of mathematical models, which are frequently no more than an excuse for occupying the terrain and masking the vacuity of the content.
Economics is a good degree to have but the subject is very theoretical at Cambridge and I found it frustrating that you can't apply a lot of the models to particular circumstances.
No good model ever accounted for all the facts, since some data was bound to be misleading if not plain wrong.
The climate-studies people who work with models always tend to overestimate their models. They come to believe models are real and forget they are only models.
Buildings are always better than drawings and models.
Models can easily become so complex that they are impenetrable, unexaminable, and virtually unalterable.
All countries are particular and no models are perfect.
All models have faults - that doesn't mean you can't use them as tools for making decisions.
All models are approximations. Essentially, all models are wrong, but some are useful. However, the approximate nature of the model must always be borne in mind.
A theory has only the alternative of being right or wrong. A model has a third possibility: it may be right, but irrelevant.
All models are false but some models are useful
In our work, we are always between Scylla and Charybdis; we may fail to abstract enough, and miss important physics, or we may abstract too much and end up with fictitious objects in our models turning into real monsters that devour us.
We have the best mathematical economic models in the world, and just because our models have been wrong for 14 straight quarters does not mean that they will be wrong in the 15th quarter.
Nothing in these abstract economic models actually works in the real world. It doesn't matter how many footnotes they put in, or how many ways they tinker around the edges. The whole enterprise is totally rotten at the core: it has no relation to reality.