Q2 Assuming the population is normally distributed and σ is unknown find the critical value for the given information: c=.95 n=12.

Answer 1

For confidence level .95, the alpha for a two-sided test (or confidence interval) is 0.025. We would find the critical value for a two-sided test (or confidence interval) from the t-table, which is +/- the critical value for an upper-tail probability of 0.025 and n-1 = 11 degrees of freedom = +/- 2.201.