Kind of an odd question, but, is this a standard equation for stats? I can't figure out for the life of me what it looks like.
$\left(\frac{\text{Sample Of A}}{\text{Population Of A}}\right)\left(\frac{\text{Population Of B}}{\text{Sample Of B}}\right)-1$ which I guess could also be written as this $$\left(\frac{X}{\sum X}\right)\left(\frac{\sum Y}{Y}\right)-1$$
Any help is greatly Appreciated.
Like Michael Hardy, I am confused by the first version of this. However, your mathematically statement that follows admits an interpretation:
$\left(\frac{X}{\sum X}\right)\left(\frac{\sum Y}{Y}\right)-1 = \frac{\frac{X}{\sum X} - \frac{Y}{\sum Y}}{\frac{Y}{\sum Y}}$.
Is is just the relative difference of the two quantities $\hat X =\frac{X}{\sum X} ,\hat Y=\frac{Y}{\sum Y}$, with respect to $\bar Y$.
This is definitely not a standard statistical equation. If the $X$ are sample values, then $\frac{\hat X - \hat Y}{\hat Y}$ will also be a random variable (before data collection), hence it appears to be a statistic.