1. Apr 5, 2005

semidevil

i'm getting my concepts very confused now...

so the formula for the normal distri is (y - u)/(sigma)/((sqroot(n)).

so if I want to test y, I set that formula = to alpha(where alpha is the confidence level).

that is if it is one sided. if it is 2 sided, do I still set it to alpha, or alpha/2?

2. Apr 12, 2005

QuantumMech

i'm pretty sure if it's 2 sided then you set it to $$\frac{\alpha}{2}$$