by Dawn Wright | Mar 29, 2018

If you are given summary data and asked to find a confidence interval, it is relatively easy using StatCrunch. Here is a typical problem: In this problem, you are told to use the t-distribution, but that may not always be the case. If you are given the sample standard...
by Dawn Wright | Nov 3, 2017

For the present, yes, the degrees of freedom you need to find values of t are going to be equal to n-1. That’s all you need to know for the midterm. Later in the course, things will get more complicated re degrees of freedom. Let me try to give a short...
by Dawn Wright | Apr 10, 2017

Consider the following problem: The grade point averages for 12 randomly selected students are shown in the table below. Find the 99% confidence interval around the population mean, ยต. Assume the population is normally distributed. Solution: This is a small sample, n...