2. The Spring 2001 Experiment

On the first day of class I explained to students that they could use either package to do the computer assignments, and briefly outlined their main advantages and disadvantages. I said that Excel is probably already installed on their computers, whereas they'd have to go to the college computer lab to use Minitab. Minitab, however, is geared to do exactly the kinds of things we'd be discussing in class, while Excel is not and would require a little more work. In fact, Excel users would first need to make sure that the "Data Analysis Toolpak" had been installed on their machines with Excel before they could perform the required analyses.

All five assignments contained instructions in both Minitab and Excel. During the class in which the first assignment came out, I demonstrated what needed to be done in both environments, which took up quite a bit of time. With subsequent assignments, I reviewed (but didn't demonstrate) the instructions emphasizing important points and differences between the packages. For example, the two packages calculate class frequencies in a histogram differently: Minitab includes values equal to the left class endpoint (but not the right endpoint) whereas Excel does just the opposite. A few students actually did some of the assignments both ways and discovered additional discrepancies between the packages, e.g., they use different terms and symbols for the same statistical concept, and have slightly different formulas for some things such as the first and third quartiles.

Assignment 1 focuses on making several histograms from a dataset with multiple columns and using these to answer questions about the distribution of the variables. The second assignment also requires students to construct histograms for several variables, as well as to examine basic descriptive statistics. Assignment 3 requires simple linear regression, while the fourth demonstrates the Central Limit Theorem by having the students randomly sample repeatedly from a large population of data. The last assignment requires the calculation of confidence intervals for the mean, in addition to performing 1-sample t-tests for the mean.