Symbol N

Its job in the formula

N is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Where the article explains it

For a population of size N with a binary response indicator R (did this person’s data reach the sample) and an outcome Y (their realized value on some Moral-Machine-relevant preference indicator), Meng’s identity relates the sample mean to the true population mean as $\bar{Y}_n$ - $\bar{Y}_N$ = $\rho_{R,Y}$$\sqrt{\frac{1-f}{f}}$\,$\sigma_Y$ , where $\rho_{R,Y}$ is the “data defect correlation” between selection and outcome across the full population, f = n/N is the sampling fraction, and $\sigma_Y$ is the outcome’s population standard deviation.

Learn the underlying idea

A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.

Open the illustrated variables: a letter stands for a value guide →