In population statistics, are variation and variance the same terms? If not, what is the difference between the two?
I know that variance is the square of standard deviation. I also know that it is a measure of how sparse the data is, and I know how to compute it.
However, I've been following a Coursera.org course called "Model Thinking", and the lecturer clearly described variance but was constantly calling it variation. That got me confused a bit.
To be fair, he always talked about computing variation of some particular instance in a population.
Could someone make it clear to me if those are interchangeable, or perhaps I'm missing something?
variance, is not the name of some specific quantity (however,
Coefficient of variationis). It is a generic term, like
variability. It is just
amount of variabilitywhich can be measured by various quantities (most popular of them being
Varianceis a real statistical term with a formal model standing behind it, but
variationis just a word describing relation between expected & real data? $\endgroup$