On this website:
both type I and II errors are accounted for by the one equation.
Surely, because a type I error involves too much positive variance and a type II error involves too much negative variance, the $2$ are mutually exclusive?
Will I not need to calculate the minimum sample size given a power of $x$ and a minimum sample size given an Alpha of $y$ and then choose the larger of the $2$ as one, the power say, is my limiting factor?
I appreciate both theoretical and practical feedback.
I'm looking for this in the context of the difference between 2 sample proportions if that makes a difference.
(In fact a longitudinal randomised control trial so 2x2)