In: Statistics and Probability
What critical value t* from Table C would you use for a confidence interval for the mean of the population in each of the following situations?
A 80 % confidence interval based on n = 20 observations
here sample size, n = 20, hence degrees of freedom, df = 20 - 1 = 19
80% CI indicates, the area in either tail of curve is 0.1
t-value = 1.328