Variance vs Variation

Question

So far both terms have always meant the same thing for me, however, I started wondering, do they mean the same thing?

The first 3 principal components explain 80% of the variance.

The first 3 principal components explain 80% of the variation.

Therefore, do both sentences have the same meaning?

Answer 1

"Variance" has a formal statistical definition. "Variation" is informal and depending on context, may mean different forms of "variability", or "spread", of the data. So they can, but doesn't have to, mean the same thing.