Confidence Intervals
60% partyA +-3% -> confidence interval 57, 63 in %.
many often confidence interval become 95% chance.
suppose we increase the sample size N, size of CI shrink.
P=0.5, μ=0.5, σ^2=0.25
mean(ΣXi), Var(ΣXi), Var(1/nΣXi), std dev, CI
n=1, 0.5, 0.25, 0.25, 0.5, 0.98
n=2, 1, 0.5, 0.125, 0.35, 0.69
n=10, 5, 2.5, 0.025, 0.16, 0.31
1.96 magic number
π 3.14
e 2.718
