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> the terms are used interchangeably in most contexts

Counting and estimating are not used interchangeably in most contexts.

> because in the real world all counting methods have some nonzero error rate.

The possibility that the counting process may be defective does not make it an estimation.

> We talk about ‘counting votes’ in elections, for example, yet when things are close we perform ‘recounts’ which we fully expect can produce slightly different numbers than the original count.

We talk about counting votes in elections because votes are counted. The fact that the process isn't perfect is a defect; this does not make it estimation.

> That means that vote counting is actually vote estimating, and recounting is just estimating with a tighter error bound.

No. Exit polling is estimation. Vote counting is counting. Vote recounting is also counting, and does not necessarily impose a tighter error bound, nor necessarily derive a different number.

> The situations where counting is not estimating are limited to the mathematical, where you can assure yourself of exhaustively never missing any item or ever mistaking one thing’s identity for another’s.

So like, computers? Regardless, this is wrong. Estimating something and counting it are not the same thing. Estimation has uncertainty, counting may have error.

This is like saying addition estimates a sum because you might get it wrong. It's just not true.




So, IEEE floating point doesn’t support ‘addition’ then.


IEEE 754 defines an exact binary result for the addition of any two floats.

That this bit-identical result is not the same operation as addition of real numbers is irrelevant, because floats aren't reals.

f1 + f2 is not an estimation. Even treating it as an approximation will get you into trouble. It's not that either, it's a floating-point result, and algorithms making heavy use of floating point had better understand precisely what f1 + f2 is going to give you if they want to obtain maximum precision and accuracy.


Cool, so next time I have numbers that aren't reals to perform math on, I can use floats.


Or if you have numbers that aren't integers to perform math on, you can use integers.

It's not a new problem, and it isn't specific to floats. Computers do discrete math. Always have, always will.




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